Allow turning off Video CDN in Studio.

BLD-1207
Annotator Tools: Fix major logic bug in code
Add Optimizely widget
Merge pull request #4760 from edx/oleg/turn-off-cdn-rc

Allow turning off Video CDN in Studio.
Merge pull request #4764 from edx/diana/show-cert-without-end-date

Show Certificates Before End
Merge pull request #4763 from edx/lms/add-optimizely

Lms/add optimizely
Merge pull request #4762 from edx/annotations-js-fix

Annotator Tools: Fix major logic bug in code (RC)
Remove banner from instructor dashboard
Reenable user partition in Advanced Settings.
Merge pull request #4775 from edx/alex/fix-reenable-user-partitions

Reenable user partition in Advanced Settings.
Doc changes for new publishing workflow
Fix for empty imsx_messageIdentifier
Merge pull request #4356 from edx/markhoeber/documentation/publishing-changes

WIP: Documentation for Publishing Changes
Merge pull request #4237 from starteam/master

Fix for empty imsx_messageIdentifier
Release Notes for 8/12/14
Merge pull request #4783 from edx/ahodges/documentation/relnotes08_12_14

Release notes - 8/12/14
Clean out the mako temp dirs before running tests
Merge pull request #4768 from edx/sarina/remove-legacy-banner

Remove banner from instructor dashboard
Ignore errors on rmtree cleanup
Studio: refactoring font-weight CSS rules to use Sass placeholders