https://openedx.atlassian.net/browse/MA-76

"As a beta user for a course, I can access the student view of a course in the app"

Also adds me as an AUTHOR
I made a change here, instead of adding another clause to the conditional inside ``mobile_course_enrollments`` because it seemed like we wanted to streamline that logic for the general case and it fit with the existing inheritance behavior for instructors. But I was a little concerned that this is actually the right semantic and in retrospect should have added a comment asking about it.

Do you think it's a reasonable change?