Put inline previews in remarkup textareas
Summary:
Ref T3967. This gives us a reasonable baseline for doing remarkup previews inline in all contexts, and works in weird/constrained context including:
- inline comments;
- conpherence; and
- custom fields.
It would be nicer to go beyond this in contexts like Phame posts, but this is a start, at least.
Test Plan:
Reviewers: chad
Reviewed By: chad
Maniphest Tasks: T3967
Differential Revision: https://secure.phabricator.com/D14855