- Removed unused imports
- Ran isort to properly order/style imports

Fix bug in url method of register page object
Add dist directories to gitignore

Added fixtures for course and xblock creation
Added bok-choy Studio tests
Added bok-choy tests for ora self- and ai- assessment
Refactored auto-auth; added staff and course-enrollment options
Removed extra javascript properties from page objects

Use the XBlock library as the base for XModule, so that we can incrementally rely on more and more of the XBlock api