The Animation package helps to schdule animations to happen at specific times.
With this package, you can start several animations at the same time, or
start animations in sequence. It also allows you to add and remove items
to the scenegraph so that they all appear to the user at the same time.
In addition, it features a TransitionManager which is a global touch-point
in the system to coordinate changes in the scene. After a user action, the
TransitionManager is responsible for triggering to models to provide updates
to the views. The views then create an animation plan, and the transition manager
coordinates all parts of the plan to deliver a polished animation to the user.