add infinity symbol to calc preview
Add more tests for the container page
Make course_id a required arg to split.create_course
and remove attempt to make it unique. Instead raise exception on dupe.
STUD-1359
Fix "Course started?" display on beta dash LMS-1548
Add common/djangoapps/third_party_auth; update pylintrc to allow test_* names.

third_party_auth contains a working settings mechanism, the start of the provider interface + 3 implementations (Google, Mozilla Persona, LinkedIn), and a stub for the auth pipeline. Modified existing lms settings files to use but deactivate the module.
Merge pull request #2850 from edx/sarina/lms-1548

Fix "Course started?" display on beta dash LMS-1548
BLD-852: Fix video positioning in full view mode.
Adjust wording around grade reports LMS-2109
Merge pull request #2813 from edx/anton/fix-transcript-in-full-screen-mode

Fix video positioning in full view mode.
Merge pull request #2858 from edx/sarina/lms-2109

Adjust wording around grade reports LMS-2109
Rename "Forum" roles on inst dash LMS-2092
Update discussions documentation LMS-2092
Merge pull request #2860 from edx/sarina/lms-2092

Rename "Forum" roles on inst dash LMS-2092
Only add mentoring application to INSTALLED_APPS when in virtualenv
Update import location of `prefer_xmodules`
Normalize the representation of Scope.content data in MongoModulestore FieldData

Without this, the new 'items' field in the course_info xmodule caused
bizarre behavior. If you added the text 'items' to a course_info
section, then the LMS would throw a 500, because the field name isn't
'data', but the stored data is a string, leading to the check of
`key.field_name in self._data`, where key.field_name is the string 'items',
and self._data is the content string.
Merge pull request #2811 from edx/andya/container-unit-tests

Add more tests for the container page
Delay import of xmodule packages until after sys.path fixup
Fix some simple pep8 and pylint violations
typo error in this file causing it to fail to install