phabricator: add a "phabstatus" show view We add a "phabstatus" show view (called as "hg show phabstatus") which renders a dag with underway revisions associated with a differential revision and displays their status. The revisions shown is a subset of that shown by "work" view, only including revisions with known by Phabricator. Differential Revision: https://phab.mercurial-scm.org/D7506