Remove association with PrepaidReviewModule

Users can be associated by student_id or instructor_id, so those
associations become difficult to define.
Prevent error when a not-logged-in user purchasaes PSRM
Add product_id to JWT sellerData
Add quantity to JWT sellerData
Refactor getJWT()
Prevent validation error when an unknown user purchases PSRM
Remove 'successful purchase' alert message
Fix missing call to PrepaidReviewModule::save()
in afterFind(), convert cost from cents into dollars

Switching cost from float to int to avoid calc errors
Add missing call to loadModel()
Fix error in getReport()
Fix how dates are returned in getReport()
Include all user data (Role association was missing earlier) in
Auth::login() parameter when user is logged in via cookie
Initial commit

Not finished
Fix cookie login code so Role data is passed to Session
Add action buttons
Add attendance_reported to retval
Add attendanceIsReported()
Pass $course_has_begun to report_attendance() view
Fix report_attendance link