R1:7bdd0e7a3dcd

More icons, black grey and white.

Summary: Added Celerity, Retina

Test Plan: Mostly Photoshop, need to test for realz.

Reviewers: epriestley, btrahan

Reviewed By: btrahan

CC: aran, Korvin

Maniphest Tasks: T2013

Differential Revision: https://secure.phabricator.com/D3954