Remove south related monky patch.
Comment/Remove generic tabular inlines.
Remove obsolete data from README
Remove now unused sql directory
Remove old south migrations.
Update requirements.
Remove now obsolete migrate_history django command.
Remove now obsolete migrate_references django command.
Remove obsolete code that uses reversion.
Remove reversion from requirements.txt
Register timeline signals in app.ready hook.
Fix settings compatibility.
Remove south and reversion from INSTALLED_APPS.
Update development dependencies.
Add pillow to requirements.
Refactor test factories to new factoryboy version (more compatible with django 1.7)
Patch client test fixture with useful login method.

This removes django-testclient-extensions because
it doesn't compatible with django 1.7.
Remove django-testclient-extensions from requirements.
Add django1.7 migrations.
Fix HistoryResourceMixin class import.