Remove autoplay for video in course about page

The iframe was generated with autoplay=1, which, sometimes, would cause
the video to play in the background.
Display only the first component name in the page (and nav) title.
STUD-1351
Move FieldDataCache assert to check both get and get_or_create
Upgrade CodeMirror to 3.21.0 (with accessibility changes from
http://bgrins.github.io/codemirror-accessible/)
LMS-1802
Remove assert stmt from i18n validate script
Increases precision of percentages shown in 'Total' bar on the progress page.

The percentages shown currently can be confusing. For example, if the true weight
of a category is 0.76925% and the student scores 100% in it, they will see '0.8%
out of a possible 1.0%'. Increasing the precision to 2 decimal places changes it
to '0.77% of a possible 0.77%'.

LMS-2205
Continue showing edit dialog until saving is complete to allow user to correct validation errors.
Removed all Push mode information

We should only support Pull mode

stud-1332
Edits from review

stud-1332
Merge pull request #2784 from edx/usman/lms2205-progress-page-inconsistency

Increases precision of percentages shown in 'Total' bar on progress page
Merge pull request #2783 from edx/sarina/remove-assert-from-validate

Remove assert stmt from i18n validate script
Merge pull request #2787 from edx/markhoeber/documentation/stud-1332

Removed all Push mode information
Corrected info about angle brackets in labels
Merge pull request #2788 from edx/sylvia/documentation/DOC-65

Corrected info about angle brackets in labels
Add bok choy tests for forum comment editing
Merge pull request #2761 from edx/jbau/add-userid-to-FieldDataCache

Move FieldDataCache assert to check both get and get_or_create
Merge pull request #2774 from edx/gprice/edit-forum-comment-bok-choy

Add bok choy tests for forum comment editing
Merge pull request #2518 from edx/dcs/a11y-code-grader

Upgrade CodeMirror to 3.21.0
Translate gender and education level from user profile
Merge pull request #2785 from edx/will/studio-oa-validation-fix

Studio OA validation dialog