Add a new waffle switch that allows us to assume zero grades for
learners who have no entry previously recorded, and another to
disable persisting grades for unengaged learners.
TNL-6691
* First take at forcing a subsection's grade to update when a signal is
sent that a problem's score has changed
* Refactor signal handler connection.
* Expand bokchoy tests to cover progress page
* Add some grading unit tests
TNL-5394
TNL-5364
Fix bok_choy test by changing course separator.
Change format of the modal title to '[Subsection/Section Name] Settings'.
Improve bok_choy test stability.
Studio: correcting modal window size name for outline settings editor
Specify full date in bok_choy tests.
Refactor bok_choy tests.
Remove .modal-editor from basic-modal.underscore
Set classes in modal window dynamically.
Studio: revising outline edit modal tip content and overall size
Rename isEditable to isEditableOnCourseOutline.
Interpolate display name.
Use graded instead of format as flag.
Studio: revising outline settings edit modal size
Fix selectors in bok_choy tests.
Change expectedFailure decorators to skip, because that still takes
a screenshot as if it were an error and at least one of those
take a super long time when running locally on devstack.
