Issue 1422 Delete language button
 Issue 1422 Delete language button
 Issue 1422 Delete Language Button
Quadrant view for scatter plot coach-report.
Added comments.
Merge remote-tracking branch 'upstream/develop' into issue1422-local

Conflicts:
	kalite/templates/updates/update_languages.html
 Resolved Merge Conflict
Adding LOGIN_URL and LOGOUT_URL; needed for login_required header.

Conflicts:
	kalite/distributed/settings.py
Disable kaserve, set up STATICFILES_DIRS, reset STATIC_ROOT to allow testing
Move coachreports static files
Moving control_panel static files.
Moving updates static files.
Move facility static files.
Move khan-exercises to distributed app.
Moving distributed static files.
Fixing missed khan-exercises path.
Moving static files to root folder, will collect to expected location using collectstatic
Remove static urls from distributed urls, as they're served by runserver directly.
Add collectstatic to setup.
re-enable kaserve funnel after removing disable of static file serving.