Re-enable the component acceptance tests
Quiet down exceptions at startup, and during tests

There's no need to display a traceback for every failed content load,
the comment before the log line even says so.

The exceptions shown before tests are run are because of the eager
initialization of the modulestores.  They don't need to be initialized
then, that just speeds the responsiveness of servers.  Putting off the
initialization means they get inited as needed, and the log lines get
Increased timeout in LaTeX acceptance test.
First pass at ARIA. Video player buttons announce themselves as button when used with a screen reader
All buttons have an ARIA role, name , and state
Volume slider announces its name and value to screen readers
Progress slider announces its nabe and value to screen readers
Disabled one test in video_quality_control
Code cleanup
Added more explanatory states to the Volume, Fullscreen, HD, and CC controls
Fixed failing test.
Addressed PR comments
No need to invoke classmethods through self.__class__
Added changes made to video.html to fixtures. Addressed latest PR comments
Catch WebDriver exceptions when creating selenium browser
Fix parentheses so that we only pull the course modes we want.
small unicode fix in instr dash
Merge pull request #1175 from edx/jmclaus_bugfix_video_player_controls_a11y

Bug fix video player controls a11y
Merge pull request #1179 from edx/zoldak/enable-component-acceptance-tests

Re-enable the component acceptance tests
Add AUTOMATIC_VERIFY_STUDENT_IDENTITY_FOR_TESTING flag so that acceptance tests can run through certificate identity verification flow.