Config re-design

Summary:
This is a full UI pass at a cleaner "Config" application. The main idea is to simplify the UI, center it, and have a different feel than other UI, a sort of "manage" UI theme for objects with loads of settings. Also adds a new minimalistic "WHITE_CONFIG" box type which may get re-used in Diffusion settings. This is a 90% pass, I'll have a few follow up diffs. Specifically:

• Build breadcrumbs as a flexible UI to go into headers.
• One click ObjectItemView option, for hover states.
• Sidenav doesn't always select (AphrontFilter issue)
• Mobile touchups, though it's pretty reasonable.

Test Plan:
Click through every page here, edit options, see new navigation UI. Test a few various setup issue layouts including fatals.

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Reviewers: epriestley

Reviewed By: epriestley

Spies: Korvin, epriestley

Differential Revision: https://secure.phabricator.com/D18519