color: change color of grep.rev label (BC) GNU grep uses green for line numbers as we do, but I sometimes get a bit confused when I do `hg grep --diff -n` and get both line numbers and revisions and don't know which one is which. A different colour can help.

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