Release Candidate

- Updated models to give the ability to "disable" cards. This way can
  can see keep cards attached to the user and still revoke them access
- Added in some more test cases, still not perfect but it's a start
- separated the SQLAlchemy database setup/tear down code into it's own
  class (now called SQLAlchemyBase). This way we can use the can code
  for scripts that use the base daatabase structure but are separate
  applications
- General code clean up and fixes