Patch write_pkg_file and read_pkg_file for higher metadata standards

def _patch_distribution_metadata():
    """Patch write_pkg_file and read_pkg_file for higher metadata standards"""
    for attr in ('write_pkg_file', 'read_pkg_file', 'get_metadata_version'):
        new_val = getattr(setuptools.dist, attr)
        setattr(distutils.dist.DistributionMetadata, attr, new_val)