.arcconfig

templater: process mapping dict by resource callables

A resource item is a callable, so let's make it look up a resource object
by itself.

{
    "conduit_uri": "https://phab.mercurial-scm.org/api",
    "repository.callsign": "HG",
    "arc.land.onto.default": "@",
    "base": "hg:.^"
}