Start linting envs files, add task to only pylint errors, and move pylintrc file to the correct location

Use setup.cfg to set up default settings when running nose tests. Enable
the rednose library to color test output.

use django caching to hold computed metadata inheritence. Also invalidate the cache entries on writes (insert, updates)

- this may not be a good idea, but needed for testing cohorts for now...

This reverts commit 793354a0.

- Add tasks to test lib without coverage
- Add a coverage flag to test.py (set to True, for manual tweaking for now)

http://slacy.com/blog/2012/04/make-your-tests-faster-in-django-1-4/

rake fasttest_lms goes from 48 to 26 seconds.

Now looks for a status_message.json file, looks for 'global' and ${course.id} keys. Return any global message and any course-specific message, joined by <br>.

fab files need to be updated to use this new format (new filename, possibly also help manage per-course messages, or at least test for valid json)

- add a check for the feature flag before trying to save user info to the service