Use new modeltranslation population option to fix untranslated fixture loading (e.g. ``createdb``) without presupposing any more translations than necessary.
Auto run ``update_generated_fields`` after loading fixtures in ``createdb``, so creating a fresh project with modeltranslation no longer requires running any additional commands (adding languages or loading untranslated fixtures still requires manual use of ``update_generated_fields``).
Populate ``required`` is enough for keywords creation.