Normalize colors a bit better on Profiles/Projects, add Workboard backgrounds

Summary: Cleans up the backgrounds a little on Projects/Profiles and adds a number of colour choices for Workboards.

Test Plan:
Manually add each color for testing. Test new project / profile layouts with and without properties.

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: Korvin

Differential Revision: https://secure.phabricator.com/D15269