Starting to make a/e table slightly more sane
classroom: Add day_{assignments,exams} function.

This allows us to get the assignments or exams for the classroom on a
given day.
user: Add "classes" function

This will give the classrooms that the user belongs to.
Heavy work on docket assignment/exam display.

While it's not perfect nor perfectly optimized, it works beautifully for
what it is as of right now.