Handle unrecognized argument exception in pycompare

#

# \returns errors: `int` Number of detected error-level inconsistencies.

def main():

    config = {}

    try:

        config = parse_arguments()

    except ValueError as ex:

        print(ex)

        print("\nType \"pycompare.py --help\" to get more detailed help.")

        exit(1)

    errors, warnings, noisy = (0, 0, 0)

    if config['help_mode'] or len(argv) == 1:

        config['help_mode'] = True

        elif (arg.startswith("--warn")):

            config['warning_threshold'] = float(split_arg[1])

        else:

            raise Exception("Unrecognized argument \'{0:s}\'".format(arg))

            raise ValueError("Unrecognized argument \'{0:s}\'".format(arg))

        arg_index += 1

    return config