Use absolute path to jQuery fallback
Update button text
Allow images in articles
Update 'How does scheduling a course work?' text
Remove /courses/add_students

The need for liability releases and (sometimes) registration fees makes
it impractical at the moment to have instructors manually add students
to classes.
Link 'register' button to /courses/register

Because duh.
Create paymentsReceived()
Pass Course::paymentsReceived() to edit view
Merge remote-tracking branch 'origin/master'