Identify published commits in working copies by using remote configuration
Ref T13546. When running "arc branches", we want to show all unpublished commits. This is often a different set of commits than "commits not present in any remote".
Attempt to identify published commits by using the permanent ref rules in Phabricator.
Test Plan: Ran "arc look published", saw sensible published commits in Git.
Maniphest Tasks: T13546
Differential Revision: https://secure.phabricator.com/D21378