Merge pull request #2381 from edx/jmclaus/feature_video_speed_control_improved_a11y

Keyboard events and ARIA markup added to speed control
Remove unused imports.
Merge pull request #2544 from edx/diana/drupal-registration-i18n

Don't internationalize strings we use for enrollment.
Merge pull request #2548 from edx/diana/drupal-registration-i18n

Don't internationalize strings we use for enrollment.
Merge pull request #2521 from edx/db/create-account-400

unit tests to handle duplicate user registration attempts
Merge pull request #2488 from edx/ned/i18n-for-wiki

Finish wiki i18n
Merge pull request #2466 from edx/christina/move-tests

Move tests related to views files into views/tests.
Fixed TOC and copyright
Merge pull request #2546 from edx/markhoeber/documentation/dev-doc-toc

Fixed TOC and copyright
Ora page object retries even if rubric doesn't load
Refactor stub implementation of LTI Provider. BLD-601.
Merge pull request #2029 from edx/oleg/lti_stub_refactor

Refactor stub implementation of LTI Provider. BLD-601.
Merge pull request #2536 from edx/will/bok-choy-coverage-name

Change bok-choy coverage XML filename
BLD-658: Add view for field type Dict in Studio.
Merge pull request #2478 from edx/anton/add-view-for-dict-in-studio

Add a view for the field type Dict in Studio.
Persist student progress in video.

Student logins to edx, plays video, selects position, closes
browser, opens video, position is restored.

BLD-385
Merge pull request #2365 from edx/anton/store-video-progress

Anton/store video progress
pep8/pylint cleanup on symmath/formula.py
Merge pull request #2549 from edx/zoldak/things-not-to-translate

Do not translate checkbox values in html files
Merge pull request #2558 from edx/will/more-robust-ora-page

Ora page object retries even if rubric doesn't load