R1:e8ca470a40e5

Cleanup Feed on Dashboards

Summary: Minor style updates, makes full width feed work.

Test Plan: test full, 1/2, 1/3 feed in dashboards.

Reviewers: btrahan, epriestley

Reviewed By: epriestley

Subscribers: epriestley, Korvin

Differential Revision: https://secure.phabricator.com/D9241