graft: abort if --date/user specified with --currentdate/currentuser (BC)
They are conflicting options. Let's explicitly ban such combination.
Note that this means you need "--no-currentdate --date" to override
--currentdate specified in aliases/defaults.
{
"conduit_uri": "https://phab.mercurial-scm.org/api",
"repository.callsign": "HG",
"arc.land.onto.default": "@",
"base": "hg:.^"
}