Summary: Fixes T12840. This adds a parallel "graph" button next to history on home and on the history list page. I'll think more about better placement of how to get to this page with the upcoming redesign that's still sitting in Pholio.
Test Plan: View History, View Graph, Try pager, go to a file, click view history, see no graph button.
Reviewers: epriestley
Reviewed By: epriestley
Subscribers: Korvin
Maniphest Tasks: T12840
Differential Revision: https://secure.phabricator.com/D18131
