Add a command to transfer students from one course to another.

Move only active students and also update cert item for verified students.
CertificateItems should be updated for all course students.

Not just students that are currently active.  Students may have enrolled with verified certs, paid, gotten
a refund, and un-enrolled from the original course.  This function should now capture that.
Save state before unenrolling student from old course.
small bugfixes for theming+sass+templates
Fix bug about draft verticals reordering.

STUD-714
Merge pull request #2135 from edx/anton/fix-video-volume-cookie

Video: Fix volume cookie.
Merge pull request #2105 from edx/christina/reorder-privates

Fix bug about draft verticals reordering.
Merge pull request #2041 from edx/feanil/transfer_students

Add a command to transfer students from one course to another.
Disabled video start and end time test
Merge pull request #2153 from edx/will/disable-video-test

Disabled video start and end time test
Disabled static pages and course team test seen to fail in master
Merge pull request #2154 from edx/will/disable-teams-and-static-tests

Disabled static pages and course team test seen to fail in master
Merge pull request #2143 from edx/jbau/sass-path-bugfix

small bugfix for theming+sass path
Update docs per Anant's feedback
Delete placeholder topic
Merge pull request #2155 from edx/sylvia/documentation/AA_updates

Sylvia/documentation/aa updates
Clean up some pre-existing formatting.
Remove unused things.
Rename DbModel to KvsFieldData.
Implement InheritanceFieldData