Created tests for invitation model implementations

Cleaned code for having no flake8 errors.

Created rating functionality.

Created end Ride functionality, and fixed bugs.

Changed values for not hardcoding (RideViewSet)

Created Join functionality to rides.

Created Update Functionality; changed data stuff

Added List functionality on RideViewSet.

Changed urls configuration.

Created C in Ride Model CRUD.

Fixed some bugs with imports.

Simplified adding a circle to a viewset.

Intializated rides app and created main model.

Created filtering functionality on circle viewset.

Created functionality to join a circle.