Every four years the World Cup turns into the biggest commercial moment in sport, and for Nike, Adidas and Puma it is showtime. Shirts fly off the shelves, retro kits find a new generation, and the ad campaigns live long in the memory of football fans. Start with the brand on the winning team's shirt. Since 1998, only once has the World Cup winner's kit maker also been the best-performing stock during the World Cup year. That was Puma back in 2006 when Italy beat France to lift the trophy ...