Uncomment thumbnail tests
Decorate test functions that require Pillow JPEG support
actually look for an image to verify that a thumbnail has been generated
Update pillow to 2.6.1
Limit Upload File Sizes to GridFS.

This commit puts a limit on the size of files that
course staff can upload to MongoDB. The limit is
enforced on the frontend in javascript as well
as backend via the /upload endpoint.

The limit is hard-coded in cms/envs/common.py and
may be changed according to the user's custom
needs.

If the user tries to upload a file that's too
large, an error message will pop up, with a
customizable url that pointing the user to an
external page with an alternate upload procedure.
This url is specified im cms/envs/common.py.
If not set, this url will not be displayed.
Move images from common to LMS that are only used in LMS

OPEN-328
Remove image that is duplicated in LMS and CMS

OPEN-328
Remove duplicate image files

spinner.gif and spinner-on-grey.gif are the same file.
Explicitly give the LMS a spinner.gif file.

OPEN-328
Move wiki icons to the LMS, where they are used

OPEN-328
Rename pl-faculty.png to placeholder-faculty.png

OPEN-328
Replace 'mit_dome.jpg' and 'simple_graph.png' with a default placeholder image
Merge pull request #6135 from edx/sarina/categorize-common-images

Clean up common/ images - moving, deleting, renaming as necessary
Fix Mako templates to use latest request context

Fixed the edX middleware to lazily create request
context for Mako templates, so that it is based on
any changes made to the request object.

Verified that with this fix the "Instructor" tab is
correctly hidden when a staff member is viewing
the course as a student.
Fix white spaces inside navigation
Support cohorting students via a CSV File.

TNL-735
add find_fixme task
Updating testing.md for find_fixme
Merge pull request #5961 from edx/dan-f/cohort-csv-upload

Upload CSV file for cohorting students
Merge pull request #6173 from edx/clytwynec/add_find_fixme_method

add find_fixme task
Change the default dir for loading xml files.
This should always be overridden by the testcases if needed.