Color Palette

Summary: Picked a set of standard colors. Based on our current Maniphest color set, but tweaked to the same hue with http://color.hailpixel.com/

Test Plan: Not intended to be end all be all, but a decent first cut. Applied to Maniphest and Tags.

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Differential Revision: https://secure.phabricator.com/D6229