* Clients check updated achievements as well as new ones
* Clients do not wait to keep checking
* Update achievement points along with everything else in EarnedAchievement.upsertFor
* Fix various bugs
Address some code review feedback
Correct error code in test
Don't try to send emails to empty addresses
Add tests for subscriptions
Add tests for Next Steps email
Fix specs
Add reason for disabled test
* 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
This test has been unstable, possibly because it was using one request instance to fire off
requests for many users. Rewrote using generators and multiple request instances with
separate cookie jars. For #3469.
