Add transition animations

Add transition animations

At this point, things look _really_ close to the original Quicktime
animation. The most significant defect is that the circle of dots
and the rotating hands have different center points. Currently,
these rotate at basically the same angular speed, which means the
hands are not pointing nicely at the dots. We should be just a
touch more clever to make the dots appear exactly as they are
pointed to by the hands.