If you see the arrow to American Apparel, look out: right next door is Space 98, a four-story building with a collection of young designer and small-label stores on the first floor, an Urban Outfitters on the second and third floors, and upstairs in The Gorbals, Williamsburg's latest foodie hit with a rooftop terrace. The chef was a contestant on the American version of Top Chef. His cooking is a bit strange but tasty: falafel with radish hummus and bacon dumplings, that idea. The Gorbals