Record the reason for a group size exception

[Evgeny Kotelnikov]

I also greatly miss an opportunity to add a comment on the Group size exceptions page with the reason for the exception. For instance; if a student is retaking the course I don't usually want him/her to work with one that takes it for the first time. But if I find two such students, I want them to work together. I need a easy way to administer this and a comments field is the solution.