Add its-phabricator from d425a5ded909ee73df53d5e6d91d28014d0be375

(hooks-its at 369c7d8a5a97ef8f074bd6c41d34e88b036f2d26)

its-phabricator is a plugin to (based on events in Gerrit) post
comments to a Phabricator instance.

Bug: T169
Change-Id: Ib906fdd94d7b06bedd0babc4e2d0f4d58ee26589