The list of cameos in The Devil Wears Prada 2 is so long it takes up an entire length of the movie screen in the end credits. The glossy, glamourous sequel invites the A-list to the world of Runway , with fashion designers, creative directors, stylists, models, Hollywood stars, comedians, creators, musicians, athletes, journalists , and authors appearing in scenes involving fashion shows, long Hamptons lunches, and VIP birthday parties. You know , Donatella Versace and Lady Gaga 's cameos are brilliant. Here's every cameo we could spot in The Devil Wears Prada 2 , a valiant task if we do say so ourselves.…