Add a package help page
Need to add a hydroportail.Rd file.
Maybe we need to move some information from the README to this file (and to another vignette file).
Bonjour, la 2ème lettre d'information du projet de forge INRAE est disponible à cette adresse : https://forge-inrae.pages.mia.inra.fr/www/post/2024-02-14-info-lettre-2/
Need to add a hydroportail.Rd file.
Maybe we need to move some information from the README to this file (and to another vignette file).