Starting with forum.
Make forum somewhat usable, display Libravatars.
Merge branch 'master' into forum
First take on connecting lessons to forum topics
Forum: styling topic view
Tweaking last post in a topic/forum column

- time since instead of datetime
- showing last active user
Forum: related lesson fixes

- lesson should not be required
- handle missing lesson better
Forum: Grouping lessons by their section on the forum post form
Forum: Defining font in textarea and inputs

Without it font would depend on the client styling too much.
Forum: Making subject input field wider
Forum: Missing translation
Forum search
Link to a forum
Allow for authenticated non super users to create posts and topics
Hide polls from post form for non superusers
Non authenticated users aren't allowed to use forum for now
Logout link
Merge branch 'master' into forum

Conflicts:
	edumed/templates/home.html
Hide category names on forum index page
Merge branch 'forum'