Carine Roitfeld released the second issue of her biannual, CR Book, during the Paris collections. Of course, she hardly needs a reason to burst into ballet, her latest obsession, but the launch party gave her one anyway. Here she is swanning around the ballroom of the Shangri-La Hotel with a hired ballerino, to cheers from Jessica Chastain, Adrien Brody, and Amanda Seyfried. (Photos by Billy Farrell/BFAnyc.com) …