Update bar colors to match icon colors

Summary: Fixes T8901 by adding in additional colors used by icons. Plus fire. Fire is cool.

Test Plan: Try out new colors in maniphest priorities.

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: Korvin

Maniphest Tasks: T8901

Differential Revision: https://secure.phabricator.com/D14020