Auto-tag students who are retaking the course

[jsorva]

I have no idea how easy this would be to implement in A+, but it would be nice to get a student tag on everyone who’s retaking the course. Perhaps one tag for students who tried and failed, and another on students who passed but are now retaking anyway.

This would be useful for a variety of purposes, including student advising, resource management, and plagiarism detection.