R1:1c3373d77d9e

Add owner to task boards, tidy UI

Summary: Displays task owner, hides grip texture.

Test Plan: Visit a board in my sandbox, grab and move things.

Reviewers: epriestley, btrahan

Reviewed By: epriestley

CC: Korvin, epriestley, aran

Differential Revision: https://secure.phabricator.com/D8246