The Toy Story trilogy represents one of the true marvels of cinema—a note-perfect run of movies that your great-grandchildren will enjoy watching as much as you did. And if history has taught us nothing else, the best possible thing to do to a perfect trilogy is keep milking it for more money. Pixar aims to do just that, and today announced plans for Toy Story 4. It’s coming in 2017, when you will be old and gray, and it will be directed by John Lasseter, who directed the franchise’s first two installments. That’s about all we know. If it ain’t broke, keep fixing it till it is, Pixar …