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

Remove unnecessary check.
Fix merge conflict

Conflicts:
	cms/djangoapps/contentstore/views/tests/test_container_page.py
	common/djangoapps/external_auth/tests/test_shib.py
	common/djangoapps/student/tests/test_login.py
	common/lib/xmodule/xmodule/modulestore/tests/django_utils.py
	common/lib/xmodule/xmodule/modulestore/tests/factories.py
	common/lib/xmodule/xmodule/modulestore/xml_importer.py
	lms/djangoapps/branding/tests.py
	lms/djangoapps/courseware/tests/test_submitting_problems.py
	lms/djangoapps/courseware/tests/test_video_handlers.py
	lms/djangoapps/instructor_task/tests/test_base.py
	lms/djangoapps/instructor_task/tests/test_integration.py

LMS-2876

Refactor get_parent_locations STUD-1663

STUD-1529

STUD-1595

This commit adds all of cms.

These keys are now objects with a limited interface, and the particular
internal representation is managed by the data storage layer (the
modulestore).

For the LMS, there should be no outward-facing changes to the system.
The keys are, for now, a change to internal representation only. For
Studio, the new serialized form of the keys is used in urls, to allow
for further migration in the future.

Co-Author: Andy Armstrong <andya@edx.org>
Co-Author: Christina Roberts <christina@edx.org>
Co-Author: David Baumgold <db@edx.org>
Co-Author: Diana Huang <dkh@edx.org>
Co-Author: Don Mitchell <dmitchell@edx.org>
Co-Author: Julia Hansbrough <julia@edx.org>
Co-Author: Nimisha Asthagiri <nasthagiri@edx.org>
Co-Author: Sarina Canelake <sarina@edx.org>

[LMS-2370]

This is the changes for STUD-1244, which introduces the ability for Studio to display
arbitrarily nested xblocks. In this change, a new container page is introduced which can
display nested xblocks. In particular, the xblock type of 'vertical' is special cased
to be shown inline as a collapsible section. The unit page is mostly unchanged, except
that container xblock's are shown as a link to their container page, rather than being
shown inline.

[LMS-1421][LMS-1517]

Updated the pagination tests to no longer use the toy course, but to instead explicitly upload the assets it needs.

 Added a new AssetsTestCase base class to own shared helper methods.

STUD-945

STUD-946
STUD-947

html page and update access use 2 different urls
GET update can get an individual update
STUD-944

Move index access into the url
Move course creation into the url
Add helper methods for testing to serialize json data and set accept header.

Add unit tests for auth

collection names

Remove _

Minor cleanup.

STUD-554

Code review feedback.

Instead, we use XModule field default values when creating an empty
XModule. Driven by this use case, we also allow for XModules to be
created in memory without being persisted to the database at all. This
necessitates a change to the Modulestore api, replacing clone_item with
create_draft and save_xmodule.

over all test runs.