add course short code to event in calendar event

The ICS feed provides a single calendar for all the user's courses. It does not include the course name anywhere in the event. This would be confusing if, for example, you had two events called "Midterm Exam" in the same week.
Added nil checker for student_only?
Added nil checker and display error when retrieving sis_user_id for username
Merge pull request #27 from grahamb/canvas156-calendar

add course short code to event in calendar event
Added functionality to accept email for username field

Will strip out the '@sfu.ca' and change the value of the textfield
Apparently Ruby methods don't apply in Javascript
Refactored

Removed on change event for sandbox checkbox since it was throwing an error in the background
Merge branch 'course_form' of github.com:ronvs/canvas-lms into ronvs-course_form

Conflicts:
	vendor/plugins/sfu_course_form/app/views/course_form/create.html.erb