edx/edx-platform — pull request #6117 by jimabramson (2014-12-02 18:40:36+00:00)
Title: WIP: implement group access enforcement in courseware

@andy-armstrong @cahrens

@dmitchell @cpennington - FYI - some performance optimizations still being worked on in here, but would appreciate any feedback / guidance on the overall logic which isn't planned to change.