“The ultimate badass introduction. Say this upon meeting someone tough and they’ll never mess with you.” That’s how no less an authority than Urban Dictionary (who said I wasn’t high-brow?!!) describes “I’m Batman!” – a film-defining movie line that seems to have been catapulted into cultural idiom status. (http://www.urbandictionary.com/define.php?term=I’m+Batman) Not sure if Michael Keaton unveiled …