Conpherence - fix a few bugs

Summary: fixes the "click edit and it clears title" bug. fixes a "upload the same image again and I get nothing" bug by making the create file codepath also copy dimensions if the file already exists, rather than making a copy sans dimensions. fixes the "title is so long it breaks the widget" bug by truncating the text AND adding some CSS to prevent it from happening.

Test Plan: messed around with a conpherence. changed the title, changed the picture, changed the crop and all worked. uploaded some long file names and verified they were truncated nicely.

Reviewers: epriestley, chad

Reviewed By: chad

CC: aran, Korvin

Maniphest Tasks: T2399

Differential Revision: https://secure.phabricator.com/D5378