In TeacherClassView, when a teacher assigns a paid course to any unenrolled
student, the view automatically enrolls those students, rather than requiring
the teacher to enroll those students manually first. Update copy throughout.
Also add back (smaller) padding to progress dots in TeacherClassView.
* 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
Removing trial subscriptions
Updating trial page copy
Adding special HoC trial
Introducing a new course prepaid property endDate, which won’t be
returned or redeemed after the date.
* Handling prepaids with strings for maxRedeemers
* Add link to TeacherCoursesView from HourOfCodeView
* Show only course instances with classrooms attached in TeacherCoursesView and StudentCoursesView
* Add event tracking to HourOfCodeView
* Add not-logged-in handling to TeacherCoursesView
* Fixed a GET prepaids bug
* Have course instances created for hour of code have hourOfCode property set to true.
