Students should be able to pause request

[mterwill]

Another one from @marcus-darden:

Circling around to students who need an extra minute is useless. Could add an option to their pause request. Request would be hidden from instructors, but visible to other students. Maybe add some indication on the student side that a request is paused.

We hashed out that even though it seems unfair, the first thing people do when they get to office hours is put themselves on the queue anyway. And the first thing a lot of students do when they get off is hop right back on. Pause may be a nice way to save everyone time and make the process more efficient.

[mterwill]

We could allow a student to pin themselves, which would move them out of the mainline request queue.