Making the django main template navigation course aware.
Course admin should be able to de-admin dicussion admins

As a global staff or course staff once you added yourself
in the discussion admins you cannot revoke it back unless
you remove yourself as course staff. Any of the course staff
member should be able to remove others from discussion admins
whether they are course staff or not.

TNL-315
Use strings instead of tuples as keys in SessionKeyValueStore

Some Django packages expect only strings as keys in the user session,
and it is also a recommended practice in the Django manual.
Merge pull request #5363 from mlkwaqas/waqas/tnl315-cannot-remove-discussion-admin

Course admin should be able to de-admin dicussion admins
Merge pull request #5335 from edx/sanchez/add_course_info_to_wiki

Making the django main template navigation course aware.
Merge pull request #5385 from rocha/use-strings-in-session-key-value-store

Use strings instead of tuples as keys in SessionKeyValueStore.
Pass _get_course_module() depth param down into modulestore get_course() instead of hard-coded zero.
Add bulk_operations wrapper around all course-query-intensive Studio views.
Merge pull request #5370 from edx/jeskew/wrap_studio_views_in_bulk_ops

Wrap studio views in bulk operations to minimize mongo calls.
Merge pull request #5276 from edx/anton/forums-topic

Change the topic of a previously posted post.
TNL-172: Change type of a previously posted post.
Make sure 'Marked as Answer/Unmark as answer' is present when thread type is question and not when thread type is discussion.