Merge Release back into master
Conflicts:
	cms/envs/aws.py
	requirements/edx/custom.txt

while 0 is less than 3, 0 means 'not in leaderboard'. So don't send a Notification is somone is in the 0th rank in social engagement

changes to make things work as expected after rebase with master branch
having notifications

completed tests and added type filter

removed organizations app

migration to delete tables

TNL-25

Fixed missing `user` context variable in dicussion course + switched to using more efficient `cached_has_permissions`

Fixed production deployment issue caused by staticfiles url replacements (see replace_static_urls/__init__.py -> replace_static_urls)

Fixed broken backbone history navigation in course mode. Moved runtime-specific settings modifications to runtime callbacks.

Reworked discussion assets management to work on production like environment (pipelines+nginx proxy)

Global setting for asynchronous ajax calls - to overcome firefox's strictness about using synchronous ajax with credentials

* Added scripts to XModule templates to start the apps..
* Added explicit call in XBlock to start required app.

Added concept of local urls - required to substitute absolute links for user profiles for relative in Apros

remove unicode thing

removed unicode file

putting unicode file back

return grades instead of complete status

added complete_status too