Add Pink, correct Indigo in base colors

Summary: Fixes T6307

Test Plan: Test UIExamples Color Pallete and Icon samples.

Reviewers: btrahan, epriestley

Reviewed By: epriestley

Subscribers: Korvin, epriestley

Maniphest Tasks: T6307

Differential Revision: https://secure.phabricator.com/D10707