Add keyboard navigation to Diffusion / Audit

Summary: This diff is really complicated, only a master programmer like myself could have accomplished it.

Test Plan: derrrrrp

Reviewers: davidreuss, nh, btrahan, jungejason

Reviewed By: jungejason

CC: aran, epriestley

Maniphest Tasks: T904

Differential Revision: https://secure.phabricator.com/D1936