Renamed Settings class to Configuration to better match what it means. Settings is still importable and is marked to be deprecated in 1.0.
Stop using crate and PyPI mirrors.
Added a configuration values system.

This also adds some advanced features like a setup classmethod to the Configuration class.
Reorganized and extended the documentation.
Switch to using invoke instead of Make.
Fixed broken package files.
Also don't raise an exception during import for the Settings class since that's now deprecated.
Added six to test requirements since invoke needs it
Fixed test method names.
Force list return value for filtered result.
use python3 compat version of django-cache-url
Fixed 1.6.x requirement.
Don't use django-discover-runner on 1.6 and up.