Also
* Instead of caching when a course is last published, we get this information
  from the CourseStructure table
* This commit introduces a mock py2neo Graph to be used for testing

soft delete video from video uploads page

TNL-5899

Add duplicate functionality for unit, sub-section and section

instructor dash course start and end

add discussion thread post preview in Discussion tab thread list sidebar

Fix missing import due to merge conflict between parallel PRs

Track grading task latency

Handle DAGs with inaccessible Subsections on Problem Score update

The user info is now updated every time a user loads the learner dashboard. Given that this is the page most learners land on after enrolling in a course, updating this cookie here will ensure that the enrollment status hash is relatively up-to-date.

ECOM-4895

This will allow the marketing site to determine if locally-stored enrollment data needs to be refreshed.

ECOM-4896

TNL-5817

Optimize max_score by moving from XModule to Descriptor

Merging release into master for hotfix-2016-11-17

Compute Attempted versus Grade of Zero

TNL-5886

TNL-5953

Simplify business hours on help modal

Additional Celery Queues

Upgrade cryptography library.

Workaround for TE-1767 aka cb() never called

Enhancements to generate_course_blocks management command

Refactor info.html page datetime rendering

submit_feedback function now conditionally sends emails.

Remove Extraneous Subsection Grade DatabaseError protection

TNL-5939