Checks for a transformations.json* file and returns the history.

def _get_transformation_history(path):
    """
    Checks for a transformations.json* file and returns the history.
    """
    trans_json = glob.glob(os.path.join(path, "transformations.json*"))
    if trans_json:
        try:
            with zopen(trans_json[0]) as f:
                return json.load(f)["history"]
        except:
            return None
    return None