NEW YORK — The street artist known as Banksy is both a known and unknown commodity. Yes, a commodity, as crass as that may sound. The famously anonymous street artist has created hundreds of artworks on public buildings and structures while successfully guarding his or her identity – a serious feat in a world where social media abounds and millions carry camera-equipped smart phones in their pockets. The artist lets the art speak for itself. Still, that hasn’t stopped some from trying to commodify Bansky’s art, which has brought six-figure prices, even topping the million-dollar mark at auction.