Temporarily avoid using pylibravatar to workaround python-pydns issues on epel6.
Fix libravatar idiosyncracy.
Turns out it doesn't really need to be that big.
Merge branch 'develop' into feature/display-invites
Use parsed dates when creating new invitations.
Use correct resource_url when doing login redirection for invitations.
Update invitation code to use the latest tahrir-api.
Remove hardcoded redirect after invitation is claimed.
Add some TODO notes.