Differential - modernize "Local Commits" table

Summary: ...also link to commits we know about in "Local Commits" and "Revision Update History" tables. Fixes T4585.

Test Plan: made a repo. made a diff (foo) and committed it (bar). made a new diff that was comprised of two local commits. noted links to (bar) in various commit hashes as expected

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: epriestley, Korvin, chad

Maniphest Tasks: T4585

Differential Revision: https://secure.phabricator.com/D8679