Summary: Adds core and apps grouping to configuration options, makes it somewhat easier to browse config options.
Test Plan: Set each option, review list. Breakdown is nearly 50/50 apps/core.
Reviewers: btrahan, epriestley
Reviewed By: epriestley
Subscribers: Korvin, epriestley
Differential Revision: https://secure.phabricator.com/D11722