Split: add schema version and drop pretty_id (was placeholder looking for purpose)
STUD-1359
Generate split test data via split
Test schema is set in each collection
Fix donwload subs for non youtube videos and non-en language.

Check for status in test.
Add test for track url.
Fix test to use cookie.
Use download_track in feature file.
Add new tests for get_transcript.
Add html5 test.
Add content check.
Add tests for available_translations dispatch.
Disable flaky cms test.
Add  w/o english transcript tests.
Add to changelog.
Update translations (autogenerated message)
Merge pull request #2951 from edx/sarina/031514-language-update

Update translations (autogenerated message)
Internationalization fixed for error msg on staff grading page.
LMS-2195
Merge pull request #2926 from edx/waheed/lms2195-localization-fix-on-staff-grading-page

Internationalization fixed for error msg on staff grading page.
Merge pull request #2786 from edx/alex/fix_download_html5_subs

Fix donwload subs for non youtube videos and non-en language.
Merge pull request #2918 from edx/dhm/meld_pretty_factory

Dhm/meld pretty factory
Initial implementation for system_manager app
Tightened up session impl
Removed unnecessary imports
Resolved merge conflicts
Added resource URIs and documentation reference
Added test harness for API calls
Added placeholder tests and fixed a couple bugs
Added EDX_API_KEY support
Added groups
Added support for creating/retrieving users.