.arcconfig

py3: byteify the decoded JSON responses upon receipt in the LFS blobstore

It got too confusing juggling r'' vs b'' across several functions.

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