make embargo template theme-able

Use "Stanford-style" theming to enable you to put your own embargo
notice up.
missing themed embargo page fails safely to unthemed
Add repsonse pagination to inline discussions
Temporarily disable CAPA problem "Check" button.

- update appropriate jasmine tests so that stubbed $postWithPrefix
respects a subset of jQuery promise API.
- add customization for checking state.
- display checking state while button is disabled.
- ensure checking state lasts for at least a second.
Updating ORA2 requirements for patch fix
Explicitly declare `tags` in dog stats increment calls
Fix source editor for the case of no CodeMirror editor.

In the HTML component, there is no longer a tabbed CodeMirror Editor. STUD-1516.
Use the correct response when using login.
Merge pull request #3253 from edx/sarina/fix-capa-calls

Explicitly declare `tags` in dog stats increment calls
Merge pull request #3244 from edx/christina/latex-bug-release

Fix source editor for the case of no CodeMirror editor.
Merge pull request #3256 from edx/diana/fix-grading-service-login

Return correct response when using _try_with_login
Revert "updated pdf viewer"

This reverts commit b0a7443570d929e705c295c1511f3188f4e41f69.
Revert refund instruction message
Merge pull request #3265 from edx/flowerhack/refund-message-patch

Revert refund instruction message
Refactor speed control.
Add fixes.
Update docstrings.
Removed unused helpers.
Fixed import of "dog_stats_api" in staff_grading_service.py.
LMS-2521
Merge pull request #3279 from edx/waheed/lms2521-staff-grading-panel-broken-fixed

Fixed import of "dog_stats_api" in staff_grading_service.py.