Currently when the phabricator extension's conduit output changes the tests
don't notice since the default vcr matcher only matches on 'method' and 'uri',
not the body.
Add a custom matcher that checks the same params are in the body (ignoring
vcr's in-built body matcher can't be used since it fails under py3 with a
"UnicodeEncodeError" on the "€ in commit message" tests.
The DREV ids have decreased since the recordings were generated against a
different phabricator instance to avoid spamming mercurial-devel.