Unit test to demonstrate bug
Deleting a private unit should remove it from the course
STUD-1962
Pull out edX into variables in password reset email
Merge pull request #4396 from Stanford-Online/kluo/theme_password_reset

Pull out edX into variables in password reset email
Merge pull request #4225 from edx/mathewpeterson/lms-opaque-keys-bugs

Testing for bugs off master for opaque-keys deprecation
LMS-2753
Merge pull request #4369 from edx/bug/stud-1962

Bug/stud 1962
Refactor split migrator
LMS-2936

Also, a bunch of ancillary cleanups.

Conflicts:
	common/lib/xmodule/xmodule/modulestore/tests/test_publish.py

Conflicts:
	cms/djangoapps/contentstore/management/commands/migrate_to_split.py
	cms/djangoapps/contentstore/management/commands/tests/test_rollback_split_course.py
	common/lib/xmodule/xmodule/modulestore/__init__.py
	common/lib/xmodule/xmodule/modulestore/mixed.py
	common/lib/xmodule/xmodule/modulestore/mongo/draft.py
	common/lib/xmodule/xmodule/modulestore/split_migrator.py
	common/lib/xmodule/xmodule/modulestore/split_mongo/split.py
	common/lib/xmodule/xmodule/modulestore/tests/test_split_migrator.py
	common/lib/xmodule/xmodule/modulestore/tests/test_split_w_old_mongo.py