Add South post_migrate signal to work with permission changes
Add utility function to check if user can see proposal author
Put permission to show proposal author in template context
Let Travis report to IRC
Fix null pointer reference
Some cleanup to display proposal author
Merge pull request #137 from EuroPython/feature/display-reviewer

Introduce dedicated permission to see proposal author
Update translations
Permissions on abstract models are not supposed to work.

At least not in production