Update classroom and gameplay Ux to surface practice levels as 3a, 3b,
etc.
Update next level logic to leverage practice levels based on per level
completion playtime thresholds.
Patrol buster and patrol buster A are live for testing.
Fix a few classroom Ux progress hover bubble info bugs.
Closes#3767
* Refactor several related endpoints and views
* Redesign EnrollmentView, add TeacherContactModal
* Add "Enrollment Status" tab to TeacherClassView
* Delete PurchaseCoursesView and related files
* Style-flatten RemoveStudentModal
* Fix error handling in ActivateLicensesModal
* TeacherCoursesView loads faster by only loading course campaigns, and not load prepaids
Partially fix ActivateLicensesModal.spec
[IN PROGRESS] Don't display deleted users
Move userID to classroom.deletedMembers on user delete (not retroactive)
Fix PDF links for course guides, remove old PDFs from repo
Remove deprecated SalesView
Remove underline for not-yet-linked student names
Only show class select when there's more than one
Ignore case when sorting student names
Use student.broadName instead of name for display and sorting
Fix initial load not showing progress after joining a course (hacky)
Fix text entry for enrollment number input
Fix enrollment statistics
Fix enrollment stats completely (and add back in per-class unenrolled count)
Add deletedMembers to classroom schema
More fixes to enrollment stats (don't count nonmember prepaids)
Don't use 0 as implicit false for openSpots
Update suggested number of credit to buy automatically
Fix classroom edit form ignoring cleared values
Add alert text when more users selected than enrollments available
Alert user when trying to assign course to unenrolled students
Alert user when assigning course to nobody
Add some tests for TeacherClassView bulk assign alerts
Fix TeacherClassView tests failing without demos
Use model/collection.fakeRequests :D
Remove unused comment
Fix handling of improperly sorted deleted users on clientside
Add test for moving deleted users to deletedMembers
Add script for moving all deleted classroom members to classroom.deletedMembers
Completely rewrite tallying up enrollment statistics
Fix some tests to not be dependent on logged-in user
Address PR comments
Fix default number of enrollments to buy
Fix i18n for not enough enrollments
Use custom error message for classroom name length
* Add script to merge existing course instances
* Have client only send one course instance creation
* Have server return existing course instance if one for the given classroom/course exists
* Remove bandaid code from ClassroomView
