Display only the first component name in the page (and nav) title.
STUD-1351
Upgrade CodeMirror to 3.21.0 (with accessibility changes from
http://bgrins.github.io/codemirror-accessible/)
LMS-1802
Continue showing edit dialog until saving is complete to allow user to correct validation errors.
Merge pull request #2518 from edx/dcs/a11y-code-grader

Upgrade CodeMirror to 3.21.0
Merge pull request #2785 from edx/will/studio-oa-validation-fix

Studio OA validation dialog
Merge pull request #2754 from edx/dcs/a11y-shorter-titles

Display only the first component name in the page (and nav) title.