What problem are you trying to solve with Submitty
If an instructor configures a course for "self-registration" and
leaves this setting in place for a long time period,
students can add themselves at any time to a "self-registration" course.

It would be useful to know how long a student has been in the course,
specifically when evaluating their completion of course gradeables that have no set deadline.

Describe the way you'd like to solve this problem

• Let's add a field to the course database to track when a student was added to the course.
• Let's also export this data when we "generate grade summaries", that produces the .json files in the raw_data directory for use with rainbow grades.
• Rainbow Grades can then (optionally) display this data and it should be available in the .csv file produced by rainbow grades.