Encode _id correctly for refactored Location
Fixing test_mixed_modulestore for opaque key changes
Fixing test_mixed_modulestore for opaque key refactoring
Add LocationKeyField definition
Changed StaticContent.compute_location to take course_key
Refactor common code into own module
Draft modulestore refactoring for opaque keys
in order to get test_publish to work.
Missing unicode string typing
Move url_reverse to BlockUsageLocator
was running via inheritance before.