Merge pull request #839 from kitan1982/master

Adds option to activate self-registration with validation
Redirect user to his workspaces page after creating one
Reordering migrations & fixing minor bugs.
Merge branch 'master' of https://github.com/claroline/CoreBundle into preparing-v3.3.0
Merge pull request #841 from maxailloud/good-redirect-after-creating-workspace

Redirect user to his workspaces page after creating one
Fixing html in workspaceusersPending.html.twig
Merge pull request #840 from ngodfraind/preparing-v3.3.0

Reordering migrations & fixing minor bugs.
Remove border on link in the notification dropdown menu
authentication update
Improving the csv import.
Removing useless comment.
Merge pull request #843 from ngodfraind/optimizing-user-csv-import

Optimizing user csv import
Merge pull request #842 from maxailloud/fix-css-issue

Remove border on link in the notification dropdown menu
Removing useless forceFlush()
Merge pull request #844 from ngodfraind/optimizing-user-csv-import

Removing useless forceFlush()
Authentication update
Merge pull request #845 from solispauwels/master

Authentication update
update user name regex verification
allow - in user name
Merge pull request #846 from solispauwels/master

allow "-" in user name