R1:2de06a5375c6

Add some more UI reminder text about draft revisions

Summary: See PHI433. This beefs up reminder texts for drafts a little bit since some users in the wild aren't always seeing/remembering the existing, fairly subtle hints.

Test Plan: Created a reivsion with `--draft`, viewed it, saw richer reminders.

Differential Revision: https://secure.phabricator.com/D19204