Book excerpt: Sneak a peek inside the NY Times bestselling diary of Jamie Kelly, who promises that everything she writes is true -- or at least as true as it needs to be.Dear Dumb Diary,Isabella is probably right. She almost always is.When I think back on all the things I've seen Angeline do, the one thing they have in common is that they're all dumb. (They're all strawberry-scented, too, but I think that's just her conditioner -- although her body might actually secrete its own strawberry scent.)But of all the dumb things she's ever done, this has got to be the dumbest. . . .