Tutors can pick their cancellation time period

[Simk-ops]

trafficstars

When volunteers fill out the tutoring application, there can be a slot to pick a cancellation time period. For example

If Tutor A's Cancellation time period is : 3hrs then the student must cancel at least 3 hrs before the session if they wish to.

[nicholaschiang]

This will be implemented very far off in the future (once we have a polished scheduling solution and such), so I'm going to add the "wontfix" label for now.