R1:c25de5e02fb4

Allow project colors to be relabeled

Summary: Fixes T5819. Adds configuration for setting color labels on projects and changing the default. Options are locked to what we make available.

Test Plan: {F1066823}

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T5819

Differential Revision: https://secure.phabricator.com/D15088