Pholio - make the form maintain client side edits between file uploads

Summary: Fixes T3553. Did it by adding some code that refreshes the File object on keyup events within a given file entry. also fixes an html derp I found trying to fix this.

Test Plan: added cool things like 'bbb' to every field and noted they were maintained when I added more files

Reviewers: btrahan

Reviewed By: btrahan

CC: aran, Korvin, chad

Maniphest Tasks: T3553

Differential Revision: https://secure.phabricator.com/D6488