This feature allows upload of video assets to S3. This requires that the
VIDEO_UPLOAD_PIPELINE setting be properly configured and that each
course be configured with a token issued by the media team for their
processing purposes (e.g. linking the video with a YouTube channel).

Co-authored-by: Greg Price <gprice@edx.org>

change the context_processor in the shopping cart to return a pointer to...

change the context_processor in the shopping cart to return a pointer to a function so that only the templates that actually need to know if the shopping cart button should be shown will actually make the database roundtrips

XBlockAsides in LMS

[PLAT-217]

Move lms.lib.xblock into lms.djangoapps.lms_xblock in preparation add database backed configuration to it

fix git_export tests

fix pep8 violation

Fix typo in cms unit test

fixes failing unit test in course_groups

Update pep8 to 1.5.7

Change openedx footer image to a non-broken link

Implements keyword sub feature for bulk emails

Check settings.FEATURES["ADVANCED_SECURITY"] first

Don't break up i18n string

Unit test speed improvements

Fix white spaces inside navigation

WL-105 Show course cards sorted by start dates, oldest first.

This commit pulls in changes from #4487 that implements keyword
substitution for bulk emails. With these changes, an instructor can
include keywords in their bulk emails which will be automatically substituted
with the corresponding value for the recepient of the email. Keywords are
of the form %%keyword%%, and the keywords implemented in this commit include:

%%USER_ID%% => anonymous_user_id
%%USER_FULLNAME%% => user profile name
%%COURSE_DISPLAY_NAME%% => display name of the course
%%COURSE_END_DATE%% => end date of the course

Client-side validations have also been implemented to ensure that only emails
with well-formed keywords can be sent.
The architecture is designed such that adding in new keywords in the future
would be relatively straight-forward.

Limit Upload File Sizes to GridFS

hotfix-2014-12-11

We do this intentionally, to preserve tracebacks