Update django-celery version requirement from 3.0.17 to 3.0.21

This was needed, because version 3.0.17 couldn't satisfy its version
requirement for pytz anymore. And this in turn caused "pip install -r
pip-frozen" to fail.
Update distribute module dependency to version 0.7.3
Add tracing setup function that returns missing bits
Fix bug with project retrieval for tracing setup

The project object wasn't actually retrieved.
Remove assembly class as requirement for tracing setup
Merge remote-tracking branch 'origin/master' into neurocity
Added missing SegmentsData migration. Added frozen state migration

In order for --auto to work again with South and to extract proper
migrations.
Use settings.py with NeuroCity settings
Remove settings_production.py.example and all dependencies on _production. Use settings.py instead