R1:13464cc56803

Clean up inline edit ui

Summary: Fixes the button spacing issue (doesn't seem related to forms?) and moves fonts and sizes over to Helvetica.

Test Plan: Submit many inline comments.

Reviewers: epriestley, btrahan

Reviewed By: epriestley

CC: aran, Korvin

Differential Revision: https://secure.phabricator.com/D5882