Requester save and submit differentiated

[kylehg]

An app has two states: in-progress and submitted. A requester should be able to Save an in-progress app and make changes until they Submit.

After submitting, they should still be able to make changes and resubmit (in order to, say, apply to another funding group), but the difference is that requesters will then be notified of every change.

The same behavior should apply for the follow-up questions