Allow EditEngine to build NUX buttons that point at the right place
- Pull the logic for building the "Create Whatever" dropdown out.
- Use it to generate NUX buttons, too.
- Use the new logic in Paste and Maniphest.
- Viewed Paste NUX, button worked.
- Viewed Maniphest NUX with multiple create forms, button worked.
Reviewers: chad, avivey
Reviewed By: avivey
Maniphest Tasks: T11812
Differential Revision: https://secure.phabricator.com/D16797