Add description/notes to schedule

[EricPedley]

Add a feature to leave a short description on each named schedule to remind yourself why you made it. For example, alternative schedules for if you don't get a class when a major restriction drops.

This might be a good use for the blank space beneath the search bar.

This idea came from a user on the feedback form. Low priority for the moment but I think it would be nice to have unless we think of a better use for all that blank space.