Display link in Revision ToC for copied or moved files

Summary:
They are present in the document so there is not reason to omit the links to
them.
They sometimes contains changed lines so the link could be actualy useful.

Test Plan: Display ToC of revision with moved and copied files.

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, epriestley, nh

Differential Revision: https://secure.phabricator.com/D1412