The New York tailored clothing shop Alton Lane, which has a body scanner that records your measurements in about 30 seconds, opened on Newbury Street Wednesday night with a stylish celebration that included cocktails, mini crab cakes, and yes, body scans. Guests at the preview party for the retailer included owners Colin Hunter and Peyton Jenkins; Prataap Patrose, of the Boston Redevelopment Authority; Boston fashion marketer Jeff Lahens; and the always stylish Joshua Janson.