OO-1042: check the boundaries of the hibernate bag before add a checkpoint, clean the velocity container and reload all data after a save...

OO-1038: better check of long without exception, try and catch in PersistingCourseGroupManager, unit tests

-no-jira: replace escaping with antisamy for group description as the description is edited with TinyMCE (which already escape special characters)

OO-1014: give the right name to identify the type of image in the repository details, fix the "grayed tone all pictures"!

OO-1015: don't log NoSuchFieldException while exporting a group, if the field don't exist, we want that it doesn't exist

OO-1008 add missing selection ordering to persisted editor instance, remove bogus restricted edit mode

OO-1004: encode softly the webdav names for group and resources to preserve as much as characters as possible

OO-1010: rewrtie the section form to be FlexiFormed, add rich text edition to the section objectives

no-jira: enhance course db to list of used categories, and accept repository entry keys as course id