Summary:
Allows you to quickly search for files within a repository. Roughly:
- We build a big tree of everything and ship it to the client.
- The client implements a bunch of Sublime-ish magic to find paths.
Test Plan: {F154007}
Reviewers: chad, btrahan
Reviewed By: btrahan
Subscribers: epriestley, zeeg
Differential Revision: https://secure.phabricator.com/D9087
