partial commit
Merge branch 'master' of https://github.com/claroline/CoreBundle into HEAD
workspaces managements |data|creator|nbr subscriber
partial commit
Merge branch 'workspaces-management' of https://github.com/easy-es/CoreBundle into workspaces-management

Conflicts:
	Entity/Workspace/AbstractWorkspace.php
migration fixed
Merge pull request #503 from easy-es/workspaces-management

feature : creator - number of subscribers - date