Rittenhouse is already packed with good ice cream spots. You’ve got 1-900–ICE CREAM for inventive soft-serve, Gran Caffe L’Aquila for premium gelato, Malai for Indian-inspired fare and Weckerly’s for classic fun. In the past five years, national chains like Van Leeuwen and Jeni’s have set up shop. So what possibly could a new kid on the block bring to the table? The answer, it turns out, is booze. Tipsy Scoop, the New York ice cream “barlour,”…