Touch up Audit/Commit List UI

Summary: Fixes a few issues. The author of the commit is more prominent / not cut off. Auditors is in a more consistent location. More space is available for reasons. Commits by themselves look much less janky. Only downside is actual Audits are now 3 lines vs. 2, but the extra space is used well.

Test Plan:
Test list of audits and commits.

Reviewers: btrahan, epriestley

Reviewed By: epriestley

Subscribers: Korvin, epriestley

Differential Revision: https://secure.phabricator.com/D11817