Keira Knightleywants you to just say no to "Photoshopped" celebrity images.She understands why you might resist her campaign. She's given in to the pressure from movie studios and fashion photographers, she's embraced the desire to be bigger and "better." But now she regrets it."I've had my body manipulated so many different times for so many different reasons, whether it's paparazzi photographers or for film posters,"...