Use ChangesetListView in Phriction

Summary: Ref T2009. Upgrade this from DetailView to ListView so we get "Highlight As", "View Unified", etc., and respect the unified diff prefernce.

Test Plan: Viewed diffs in Phriction.

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: epriestley

Maniphest Tasks: T2009

Differential Revision: https://secure.phabricator.com/D12013