Add Draft module store that is used whenever any item is update in the CAS (but not during import, and not for templates)

respond to Cale pull request comments. Update access.py (LMS) to use the same 'check for legacy group name first' logic. Add SECRET_KEY setting to the CAS project so that auth tokens from CAS are accepted in the LMS

adhere to the naming conventions of user groups (instructor_* and staff_* of the LMS AuthZ implementation). While we're keeping our authz.py implementation - which is duplicative of LMS's access.py - in order to minimize code churn/risk-of-regression, there is data compatibility so the two systems will interpret the data the same way

* make logging work properly in cms, dev
* fix a comment

Add tests for the edit page for the toy course, and make sure that exporting to github sets up the git repo properly

* Enable account creation
* Some code cleanups
* Fix access to nonexistent fields in the account creation view
* Formatting fixes

Acknowledge the fact that right now keystore is really just a module store. If we need a keystore that returns other objects, we can reexctract the base class into it's own module again