Parse the arguments, and pass the config object on to run.

def main(args=sys.argv):
    """Parse the arguments, and pass the config object on to run."""
    # Don't make changes to sys.argv
    args = list(args)

    # Remove arg[0]
    args.pop(0)

    # Pop off the options
    clear_opt = False
    if '-c' in args:
        args.remove('-c')
        clear_opt = True
    elif '--clear' in args:
        args.remove('--clear')
        clear_opt = True

    if len(args) == 0:
        cfg_path = os.path.expanduser('~/.wallsrc')
    elif len(args) == 1:
        cfg_path = args[0]
    else:
        stderr_and_exit('Usage: walls [-c] [config_file]\n')

    config = load_config(cfg_path)

    run(config, clear_opt)