Merge branch '38-cache_improve' into 'develop'

Enh: add summary_modifier to source function

See merge request !55

scenes/core.py

@@ -383,7 +383,8 @@ class CommonImagerySource(Source):
             self,
             temporary_directory: str = None,
             extension: str = None,
-            pixel_type: str = None
+            pixel_type: str = None,
+            summary_modifier: Callable = None
     ) -> CommonImagerySource:
         """
         Return the source cached.
@@ -393,15 +394,20 @@ class CommonImagerySource(Source):
                 Default is system temp directory.
             extension: file extension (default: .tif)
             pixel_type: pixel type
+            summary_modifier: summary modifier
 
         Returns:
             Cached source
 
         """
         return self.new_source(
-            Cache(pyotb_output=self, temporary_directory=temporary_directory,
-                  extension=extension,
-                  pixel_type=pixel_type))
+            Cache(
+                pyotb_output=self,
+                temporary_directory=temporary_directory,
+                extension=extension,
+                pixel_type=pixel_type,
+                summary_modifier=summary_modifier
+            ))
 
 
 class Scene(ABC):