Code cleaning

[ehmatthes]

• [ ] all references to previous taxonomy
  • [ ] grep entire codebase
  • [ ] references to previous taxonomy in css
• [ ] diagnostic print statements
  • [ ] views.py, test_views.py
• [ ] reorganize helper functions in views.py
  • [ ] more consistent; more efficient; move to separate file
  • [x] streamline approach to working with cas.
  • every ca has a subject area; no need to do sda_cas separately.
  • get all cas for an sa, then in template display according to whether a ca has an sda or not.
  • makes eus much easier to deal with as well.