diff --git a/.dockerignore b/.dockerignore
index 317dee225192ec7dc01c3d21b86167e0e32b5407..8c0c2089c599bbefcb6c41ea2113d2f0a77e71e5 100644
--- a/.dockerignore
+++ b/.dockerignore
@@ -2,3 +2,4 @@
 /dist/
 /node_modules/
 /.?*
+.git
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 3faa3a28849ad17ae4c6f0ad3e645788d3527e42..3aac0b2b24bb0b6741a3c43b6a55e9efbc5372df 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,6 +1,9 @@
 stages:
   - build
 
+variables:
+  GIT_SUBMODULE_STRATEGY: recursive
+
 build:
   image: gitlab-registry.irstea.fr/pole-is/docker/docker-ci:dind
   tags: [dind]
diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000000000000000000000000000000000000..1c214185c9eb07382aa5cf78794f7eca32f182fc
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,6 @@
+[submodule "external/reveal.js"]
+    path = external/reveal.js
+    url = ../reveal.js
+    update = checkout
+    branch = irstea
+    shallow = true
diff --git a/Dockerfile b/Dockerfile
index d8603967f22951fd8e8866fe5eb3b37e67c8d0af..b1cc2eb1397e1d7fb2d1aa09c471bd18b9e1457c 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,12 +1,10 @@
-FROM node
-
-RUN mkdir -p /src /dist /reveal_js
-RUN ln -snf /src /reveal_js/src
-RUN ln -snf /dist /reveal_js/dist
+FROM node:10 AS builder
 
 RUN umask 0044
 
-COPY package*.json /reveal_js/
+RUN mkdir -p /reveal_js
+
+COPY package*.json external Gruntfile.js /reveal_js/
 
 WORKDIR /reveal_js
 
@@ -16,12 +14,23 @@ ARG PANDOC_VERSION=2.7.3
 
 ADD https://github.com/jgm/pandoc/releases/download/${PANDOC_VERSION}/pandoc-${PANDOC_VERSION}-linux.tar.gz /tmp/pandoc.tar.gz
 
-RUN tar xvfz /tmp/pandoc.tar.gz -C /usr/local --strip-components=1 \
-    && rm /tmp/pandoc.tar.gz
+RUN tar xvfz /tmp/pandoc.tar.gz -C /usr/local --strip-components=1
+
+RUN chmod -R +rX /reveal_js/node_modules/.bin/* /usr/local/bin/*
+
+FROM node:10
 
-COPY . /reveal_js
+COPY --from=builder /reveal_js /reveal_js/
+COPY --from=builder /usr/local/bin/* /usr/local/bin/
+
+RUN mkdir -p /src /dist
+RUN ln -snf /src /reveal_js/src
+RUN ln -snf /dist /reveal_js/dist
+
+WORKDIR /reveal_js
 
-RUN chmod -R +rX /reveal_js /usr/local
+RUN pandoc --version
+RUN node_modules/.bin/grunt --version
 
 EXPOSE 80/tcp 8899/tcp
 
diff --git a/external/reveal.js b/external/reveal.js
new file mode 160000
index 0000000000000000000000000000000000000000..a21b758e7fcd612d541bbcbbd978a7d20f1f8108
--- /dev/null
+++ b/external/reveal.js
@@ -0,0 +1 @@
+Subproject commit a21b758e7fcd612d541bbcbbd978a7d20f1f8108
diff --git a/package-lock.json b/package-lock.json
index 5f11301835bb94c6078e6d5181d5822ecafd6052..7ca6f8f5b72e2786cc1d72e269255645c7e10cfd 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -220,9 +220,9 @@
       "integrity": "sha1-7GphrlZIDAw8skHJVhjiCJL5Zyo="
     },
     "async-each": {
-      "version": "1.0.2",
-      "resolved": "https://registry.npmjs.org/async-each/-/async-each-1.0.2.tgz",
-      "integrity": "sha512-6xrbvN0MOBKSJDdonmSSz2OwFSgxRaVtBDes26mj9KIGtDo+g9xosFRSC+i1gQh2oAN/tQ62AI/pGZGQjVOiRg=="
+      "version": "1.0.3",
+      "resolved": "https://registry.npmjs.org/async-each/-/async-each-1.0.3.tgz",
+      "integrity": "sha512-z/WhQ5FPySLdvREByI2vZiTWwCnF0moMJ1hK9YQwDTHKh6I7/uSckMetoRGb5UBZPC1z0jlw+n/XCgjeH7y1AQ=="
     },
     "atob": {
       "version": "2.1.2",
@@ -289,6 +289,15 @@
       "resolved": "https://registry.npmjs.org/binary-extensions/-/binary-extensions-1.13.1.tgz",
       "integrity": "sha512-Un7MIEDdUC5gNpcGDV97op1Ywk748MpHcFTHoYs6qnj1Z3j7I53VG3nwZhKzoBZmbdRNnb6WRdFlwl7tSDuZGw=="
     },
+    "bindings": {
+      "version": "1.5.0",
+      "resolved": "https://registry.npmjs.org/bindings/-/bindings-1.5.0.tgz",
+      "integrity": "sha512-p2q/t/mhvuOj/UeLlV6566GD/guowlr0hHxClI0W9m7MWYkL1F0hLo+0Aexs9HSPCtR1SXQ0TD3MMKrXZajbiQ==",
+      "optional": true,
+      "requires": {
+        "file-uri-to-path": "1.0.0"
+      }
+    },
     "body": {
       "version": "5.1.0",
       "resolved": "https://registry.npmjs.org/body/-/body-5.1.0.tgz",
@@ -792,9 +801,9 @@
       }
     },
     "ecstatic": {
-      "version": "3.3.1",
-      "resolved": "https://registry.npmjs.org/ecstatic/-/ecstatic-3.3.1.tgz",
-      "integrity": "sha512-/rrctvxZ78HMI/tPIsqdvFKHHscxR3IJuKrZI2ZoUgkt2SiufyLFBmcco+aqQBIu6P1qBsUNG3drAAGLx80vTQ==",
+      "version": "3.3.2",
+      "resolved": "https://registry.npmjs.org/ecstatic/-/ecstatic-3.3.2.tgz",
+      "integrity": "sha512-fLf9l1hnwrHI2xn9mEDT7KIi22UDqA2jaCwyCbSUJh9a1V+LEUSL/JO/6TIz/QyuBURWUHrFL5Kg2TtO1bkkog==",
       "requires": {
         "he": "^1.1.1",
         "mime": "^1.6.0",
@@ -818,12 +827,11 @@
       }
     },
     "error": {
-      "version": "7.0.2",
-      "resolved": "https://registry.npmjs.org/error/-/error-7.0.2.tgz",
-      "integrity": "sha1-pfdf/02ZJhJt2sDqXcOOaJFTywI=",
+      "version": "7.2.1",
+      "resolved": "https://registry.npmjs.org/error/-/error-7.2.1.tgz",
+      "integrity": "sha512-fo9HBvWnx3NGUKMvMwB/CBCMMrfEJgbDTVDEkPygA3Bdd3lM1OyCd+rbQ8BwnpF6GdVeOLDNmyL4N5Bg80ZvdA==",
       "requires": {
-        "string-template": "~0.2.1",
-        "xtend": "~4.0.0"
+        "string-template": "~0.2.1"
       }
     },
     "error-ex": {
@@ -850,9 +858,9 @@
       "integrity": "sha1-j2G3XN4BKy6esoTUVFWDtWQ7Yas="
     },
     "eventemitter3": {
-      "version": "3.1.0",
-      "resolved": "https://registry.npmjs.org/eventemitter3/-/eventemitter3-3.1.0.tgz",
-      "integrity": "sha512-ivIvhpq/Y0uSjcHDcOIccjmYjGLcP09MFGE7ysAwkAvkXfpZlC985pH2/ui64DKazbTW/4kN3yqozUxlXzI6cA=="
+      "version": "4.0.0",
+      "resolved": "https://registry.npmjs.org/eventemitter3/-/eventemitter3-4.0.0.tgz",
+      "integrity": "sha512-qerSRB0p+UDEssxTtm6EDKcE7W4OaoisfIMl4CngyEhjpYglocpNg6UEqCvemdGhosAsg4sO2dXJOdyBifPGCg=="
     },
     "execa": {
       "version": "1.0.0",
@@ -1066,6 +1074,12 @@
       "resolved": "https://registry.npmjs.org/file-sync-cmp/-/file-sync-cmp-0.1.1.tgz",
       "integrity": "sha1-peeo/7+kk7Q7kju9TKiaU7Y7YSs="
     },
+    "file-uri-to-path": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/file-uri-to-path/-/file-uri-to-path-1.0.0.tgz",
+      "integrity": "sha512-0Zt+s3L7Vf1biwWZ29aARiVYLx7iMGnEUl9x33fbB/j3jR81u/O2LbqK+Bm1CDSNDKVtJ/YjwY7TUd5SkeLQLw==",
+      "optional": true
+    },
     "filename-regex": {
       "version": "2.0.1",
       "resolved": "https://registry.npmjs.org/filename-regex/-/filename-regex-2.0.1.tgz",
@@ -1130,11 +1144,11 @@
       "dev": true
     },
     "follow-redirects": {
-      "version": "1.7.0",
-      "resolved": "https://registry.npmjs.org/follow-redirects/-/follow-redirects-1.7.0.tgz",
-      "integrity": "sha512-m/pZQy4Gj287eNy94nivy5wchN3Kp+Q5WgUPNy5lJSZ3sgkVKSYV/ZChMAQVIgx1SqfZ2zBZtPA2YlXIWxxJOQ==",
+      "version": "1.10.0",
+      "resolved": "https://registry.npmjs.org/follow-redirects/-/follow-redirects-1.10.0.tgz",
+      "integrity": "sha512-4eyLK6s6lH32nOvLLwlIOnr9zrL8Sm+OvW4pVTJNoXeGzYIkHVf+pADQi+OJ0E67hiuSLezPVPyBcIZO50TmmQ==",
       "requires": {
-        "debug": "^3.2.6"
+        "debug": "^3.0.0"
       }
     },
     "for-in": {
@@ -1164,13 +1178,14 @@
       "integrity": "sha1-FQStJSMVjKpA20onh8sBQRmU6k8="
     },
     "fsevents": {
-      "version": "1.2.7",
-      "resolved": "https://registry.npmjs.org/fsevents/-/fsevents-1.2.7.tgz",
-      "integrity": "sha512-Pxm6sI2MeBD7RdD12RYsqaP0nMiwx8eZBXCa6z2L+mRHm2DYrOYwihmhjpkdjUHwQhslWQjRpEgNq4XvBmaAuw==",
+      "version": "1.2.11",
+      "resolved": "https://registry.npmjs.org/fsevents/-/fsevents-1.2.11.tgz",
+      "integrity": "sha512-+ux3lx6peh0BpvY0JebGyZoiR4D+oYzdPZMKJwkZ+sFkNJzpL7tXc/wehS49gUAxg3tmMHPHZkA8JU2rhhgDHw==",
       "optional": true,
       "requires": {
-        "nan": "^2.9.2",
-        "node-pre-gyp": "^0.10.0"
+        "bindings": "^1.5.0",
+        "nan": "^2.12.1",
+        "node-pre-gyp": "*"
       },
       "dependencies": {
         "abbrev": {
@@ -1212,7 +1227,7 @@
           }
         },
         "chownr": {
-          "version": "1.1.1",
+          "version": "1.1.3",
           "bundled": true,
           "optional": true
         },
@@ -1237,11 +1252,11 @@
           "optional": true
         },
         "debug": {
-          "version": "2.6.9",
+          "version": "3.2.6",
           "bundled": true,
           "optional": true,
           "requires": {
-            "ms": "2.0.0"
+            "ms": "^2.1.1"
           }
         },
         "deep-extend": {
@@ -1260,11 +1275,11 @@
           "optional": true
         },
         "fs-minipass": {
-          "version": "1.2.5",
+          "version": "1.2.7",
           "bundled": true,
           "optional": true,
           "requires": {
-            "minipass": "^2.2.1"
+            "minipass": "^2.6.0"
           }
         },
         "fs.realpath": {
@@ -1288,7 +1303,7 @@
           }
         },
         "glob": {
-          "version": "7.1.3",
+          "version": "7.1.6",
           "bundled": true,
           "optional": true,
           "requires": {
@@ -1314,7 +1329,7 @@
           }
         },
         "ignore-walk": {
-          "version": "3.0.1",
+          "version": "3.0.3",
           "bundled": true,
           "optional": true,
           "requires": {
@@ -1331,7 +1346,7 @@
           }
         },
         "inherits": {
-          "version": "2.0.3",
+          "version": "2.0.4",
           "bundled": true,
           "optional": true
         },
@@ -1367,7 +1382,7 @@
           "optional": true
         },
         "minipass": {
-          "version": "2.3.5",
+          "version": "2.9.0",
           "bundled": true,
           "optional": true,
           "requires": {
@@ -1376,11 +1391,11 @@
           }
         },
         "minizlib": {
-          "version": "1.2.1",
+          "version": "1.3.3",
           "bundled": true,
           "optional": true,
           "requires": {
-            "minipass": "^2.2.1"
+            "minipass": "^2.9.0"
           }
         },
         "mkdirp": {
@@ -1392,22 +1407,22 @@
           }
         },
         "ms": {
-          "version": "2.0.0",
+          "version": "2.1.2",
           "bundled": true,
           "optional": true
         },
         "needle": {
-          "version": "2.2.4",
+          "version": "2.4.0",
           "bundled": true,
           "optional": true,
           "requires": {
-            "debug": "^2.1.2",
+            "debug": "^3.2.6",
             "iconv-lite": "^0.4.4",
             "sax": "^1.2.4"
           }
         },
         "node-pre-gyp": {
-          "version": "0.10.3",
+          "version": "0.14.0",
           "bundled": true,
           "optional": true,
           "requires": {
@@ -1420,7 +1435,7 @@
             "rc": "^1.2.7",
             "rimraf": "^2.6.1",
             "semver": "^5.3.0",
-            "tar": "^4"
+            "tar": "^4.4.2"
           }
         },
         "nopt": {
@@ -1433,12 +1448,20 @@
           }
         },
         "npm-bundled": {
-          "version": "1.0.5",
+          "version": "1.1.1",
+          "bundled": true,
+          "optional": true,
+          "requires": {
+            "npm-normalize-package-bin": "^1.0.1"
+          }
+        },
+        "npm-normalize-package-bin": {
+          "version": "1.0.1",
           "bundled": true,
           "optional": true
         },
         "npm-packlist": {
-          "version": "1.2.0",
+          "version": "1.4.7",
           "bundled": true,
           "optional": true,
           "requires": {
@@ -1500,7 +1523,7 @@
           "optional": true
         },
         "process-nextick-args": {
-          "version": "2.0.0",
+          "version": "2.0.1",
           "bundled": true,
           "optional": true
         },
@@ -1537,7 +1560,7 @@
           }
         },
         "rimraf": {
-          "version": "2.6.3",
+          "version": "2.7.1",
           "bundled": true,
           "optional": true,
           "requires": {
@@ -1560,7 +1583,7 @@
           "optional": true
         },
         "semver": {
-          "version": "5.6.0",
+          "version": "5.7.1",
           "bundled": true,
           "optional": true
         },
@@ -1606,17 +1629,17 @@
           "optional": true
         },
         "tar": {
-          "version": "4.4.8",
+          "version": "4.4.13",
           "bundled": true,
           "optional": true,
           "requires": {
             "chownr": "^1.1.1",
             "fs-minipass": "^1.2.5",
-            "minipass": "^2.3.4",
-            "minizlib": "^1.1.1",
+            "minipass": "^2.8.6",
+            "minizlib": "^1.2.1",
             "mkdirp": "^0.5.0",
             "safe-buffer": "^5.1.2",
-            "yallist": "^3.0.2"
+            "yallist": "^3.0.3"
           }
         },
         "util-deprecate": {
@@ -1638,7 +1661,7 @@
           "optional": true
         },
         "yallist": {
-          "version": "3.0.3",
+          "version": "3.1.1",
           "bundled": true,
           "optional": true
         }
@@ -1773,9 +1796,9 @@
       }
     },
     "graceful-fs": {
-      "version": "4.1.15",
-      "resolved": "https://registry.npmjs.org/graceful-fs/-/graceful-fs-4.1.15.tgz",
-      "integrity": "sha512-6uHUhOPEBgQ24HM+r6b/QwWfZq+yiFcipKFrOFiBEnWdy5sdzYoi+pJeQaPI5qOLRFqWmAXUPQNsielzdLoecA=="
+      "version": "4.2.3",
+      "resolved": "https://registry.npmjs.org/graceful-fs/-/graceful-fs-4.2.3.tgz",
+      "integrity": "sha512-a30VEBm4PEdx1dRB7MFK7BejejvCvBronbLjht+sHuGYj8PHs7M/5Z+rt5lw551vZ7yfTCj4Vuyy3mSJytDWRQ=="
     },
     "grunt": {
       "version": "1.0.4",
@@ -1842,12 +1865,17 @@
       },
       "dependencies": {
         "async": {
-          "version": "2.6.2",
-          "resolved": "https://registry.npmjs.org/async/-/async-2.6.2.tgz",
-          "integrity": "sha512-H1qVYh1MYhEEFLsP97cVKqCGo7KfCyTt6uEWqsTBr9SO84oK9Uwbyd/yCW+6rKJLHksBNUVWZDAjfS+Ccx0Bbg==",
+          "version": "2.6.3",
+          "resolved": "https://registry.npmjs.org/async/-/async-2.6.3.tgz",
+          "integrity": "sha512-zflvls11DCy+dQWzTW2dzuilv8Z5X/pjfmZOWba6TNIVDm+2UDaJmXSOXlasHKfNBs8oo3M0aT50fDEWfKZjXg==",
           "requires": {
-            "lodash": "^4.17.11"
+            "lodash": "^4.17.14"
           }
+        },
+        "lodash": {
+          "version": "4.17.15",
+          "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.15.tgz",
+          "integrity": "sha512-8xOcRHvCjnocdS5cpwXQXVzmmh5e5+saE2QGoeQmbKmRS6J3VQppPOIt0MnmE+4xlZoumy0GPG0D0MVIQbNA1A=="
         }
       }
     },
@@ -1959,11 +1987,18 @@
       },
       "dependencies": {
         "async": {
-          "version": "2.6.2",
-          "resolved": "https://registry.npmjs.org/async/-/async-2.6.2.tgz",
-          "integrity": "sha512-H1qVYh1MYhEEFLsP97cVKqCGo7KfCyTt6uEWqsTBr9SO84oK9Uwbyd/yCW+6rKJLHksBNUVWZDAjfS+Ccx0Bbg==",
+          "version": "2.6.3",
+          "resolved": "https://registry.npmjs.org/async/-/async-2.6.3.tgz",
+          "integrity": "sha512-zflvls11DCy+dQWzTW2dzuilv8Z5X/pjfmZOWba6TNIVDm+2UDaJmXSOXlasHKfNBs8oo3M0aT50fDEWfKZjXg==",
           "requires": {
-            "lodash": "^4.17.11"
+            "lodash": "^4.17.14"
+          },
+          "dependencies": {
+            "lodash": {
+              "version": "4.17.15",
+              "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.15.tgz",
+              "integrity": "sha512-8xOcRHvCjnocdS5cpwXQXVzmmh5e5+saE2QGoeQmbKmRS6J3VQppPOIt0MnmE+4xlZoumy0GPG0D0MVIQbNA1A=="
+            }
           }
         }
       }
@@ -2026,16 +2061,16 @@
       "integrity": "sha512-7T/BxH19zbcCTa8XkMlbK5lTo1WtgkFi3GvdWEyNuc4Vex7/9Dqbnpsf4JMydcfj9HCg4zUWFTL3Za6lapg5/w=="
     },
     "http-parser-js": {
-      "version": "0.5.0",
-      "resolved": "https://registry.npmjs.org/http-parser-js/-/http-parser-js-0.5.0.tgz",
-      "integrity": "sha512-cZdEF7r4gfRIq7ezX9J0T+kQmJNOub71dWbgAXVHDct80TKP4MCETtZQ31xyv38UwgzkWPYF/Xc0ge55dW9Z9w=="
+      "version": "0.4.10",
+      "resolved": "https://registry.npmjs.org/http-parser-js/-/http-parser-js-0.4.10.tgz",
+      "integrity": "sha1-ksnBN0w1CF912zWexWzCV8u5P6Q="
     },
     "http-proxy": {
-      "version": "1.17.0",
-      "resolved": "https://registry.npmjs.org/http-proxy/-/http-proxy-1.17.0.tgz",
-      "integrity": "sha512-Taqn+3nNvYRfJ3bGvKfBSRwy1v6eePlm3oc/aWVxZp57DQr5Eq3xhKJi7Z4hZpS8PC3H4qI+Yly5EmFacGuA/g==",
+      "version": "1.18.0",
+      "resolved": "https://registry.npmjs.org/http-proxy/-/http-proxy-1.18.0.tgz",
+      "integrity": "sha512-84I2iJM/n1d4Hdgc6y2+qY5mDaz2PUVjlg9znE9byl+q0uC3DeByqBGReQu5tpLK0TAqTIXScRUV+dg7+bUPpQ==",
       "requires": {
-        "eventemitter3": "^3.0.0",
+        "eventemitter3": "^4.0.0",
         "follow-redirects": "^1.0.0",
         "requires-port": "^1.0.0"
       }
@@ -2234,12 +2269,9 @@
       "dev": true
     },
     "is-finite": {
-      "version": "1.0.2",
-      "resolved": "https://registry.npmjs.org/is-finite/-/is-finite-1.0.2.tgz",
-      "integrity": "sha1-zGZ3aVYCvlUO8R6LSqYwU0K20Ko=",
-      "requires": {
-        "number-is-nan": "^1.0.0"
-      }
+      "version": "1.1.0",
+      "resolved": "https://registry.npmjs.org/is-finite/-/is-finite-1.1.0.tgz",
+      "integrity": "sha512-cdyMtqX/BOqqNBBiKlIVkytNHm49MtMlYyn1zxzvJKWmFMlGzm+ry5BBfYyeY9YmNKbRSo/o7OX9w9ale0wg3w=="
     },
     "is-fullwidth-code-point": {
       "version": "1.0.0",
@@ -2814,9 +2846,9 @@
       }
     },
     "nan": {
-      "version": "2.13.2",
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@@ -3211,27 +3243,27 @@
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+      "resolved": "https://registry.npmjs.org/portfinder/-/portfinder-1.0.25.tgz",
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-        "debug": "^2.2.0",
-        "mkdirp": "0.5.x"
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+          "resolved": "https://registry.npmjs.org/async/-/async-2.6.3.tgz",
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-            "ms": "2.0.0"
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-          "resolved": "https://registry.npmjs.org/ms/-/ms-2.0.0.tgz",
-          "integrity": "sha1-VgiurfwAvmwpAd9fmGF4jeDVl8g="
+        "lodash": {
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+          "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.15.tgz",
+          "integrity": "sha512-8xOcRHvCjnocdS5cpwXQXVzmmh5e5+saE2QGoeQmbKmRS6J3VQppPOIt0MnmE+4xlZoumy0GPG0D0MVIQbNA1A=="
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@@ -3245,6 +3277,12 @@
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+    "prettier": {
+      "version": "1.19.1",
+      "resolved": "https://registry.npmjs.org/prettier/-/prettier-1.19.1.tgz",
+      "integrity": "sha512-s7PoyDv/II1ObgQunCbB9PdLmUcBZcnWOcxDh7O0N/UwDEsHyqkW+Qh28jW+mVuCdx7gLB0BotYI1Y6uI9iyew==",
+      "dev": true
+    },
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@@ -3359,9 +3397,9 @@
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-      "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
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+      "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.7.tgz",
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@@ -3373,11 +3411,11 @@
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-      "resolved": "https://registry.npmjs.org/readdirp/-/readdirp-3.2.0.tgz",
-      "integrity": "sha512-crk4Qu3pmXwgxdSgGhgA/eXiJAPQiX4GMOZZMXnqKxHX7TaoL+3gQVo/WeuAiogr07DpnfjIMpXXa+PAIvwPGQ==",
+      "version": "3.3.0",
+      "resolved": "https://registry.npmjs.org/readdirp/-/readdirp-3.3.0.tgz",
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-        "picomatch": "^2.0.4"
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@@ -3512,8 +3550,7 @@
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     },
     "reveal.js": {
-      "version": "git+https://gitlab.irstea.fr/guillaume.perreal/reveal.js.git#a21b758e7fcd612d541bbcbbd978a7d20f1f8108",
-      "from": "git+https://gitlab.irstea.fr/guillaume.perreal/reveal.js.git#irstea"
+      "version": "file:external/reveal.js"
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@@ -3965,9 +4002,9 @@
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-          "resolved": "https://registry.npmjs.org/qs/-/qs-6.7.0.tgz",
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+          "version": "6.9.1",
+          "resolved": "https://registry.npmjs.org/qs/-/qs-6.9.1.tgz",
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@@ -4141,11 +4178,12 @@
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-      "resolved": "https://registry.npmjs.org/websocket-driver/-/websocket-driver-0.7.0.tgz",
-      "integrity": "sha1-DK+dLXVdk67gSdS90NP+LMoqJOs=",
+      "version": "0.7.3",
+      "resolved": "https://registry.npmjs.org/websocket-driver/-/websocket-driver-0.7.3.tgz",
+      "integrity": "sha512-bpxWlvbbB459Mlipc5GBzzZwhoZgGEZLuqPaR0INBGnPAY1vdBX6hPnoFXiw+3yWxDuHyQjO2oXTMyS8A5haFg==",
       "requires": {
-        "http-parser-js": ">=0.4.0",
+        "http-parser-js": ">=0.4.0 <0.4.11",
+        "safe-buffer": ">=5.1.0",
         "websocket-extensions": ">=0.1.1"
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@@ -4220,11 +4258,6 @@
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-    "xtend": {
-      "version": "4.0.1",
-      "resolved": "https://registry.npmjs.org/xtend/-/xtend-4.0.1.tgz",
-      "integrity": "sha1-pcbVMr5lbiPbgg77lDofBJmNY68="
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diff --git a/package.json b/package.json
index 2b6ca66a04a1861151e4bedd8907a297d14799db..daae8b30b3411badbd23af0854253b69e27114ec 100644
--- a/package.json
+++ b/package.json
@@ -27,13 +27,13 @@
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     "grunt-watcher": "^1.0.0",
     "readdirp": "^3.2.0",
-    "reveal.js": "git+https://gitlab.irstea.fr/guillaume.perreal/reveal.js.git#irstea"
+    "reveal.js": "file://./external/reveal.js"
   },
   "devDependencies": {
     "husky": "^1.3.1",
     "lint-staged": "^8.2.1",
     "load-grunt-tasks": "^5.1.0",
-    "prettier": "^6.5.1"
+    "prettier": "^1.19.0"
   },
   "husky": {
     "pre-commit": "lint-staged"