partial impl of FrameAnimator

This is a partial implementation of the *FrameAnimator* class. I'm testing a midlet that calls the methods I've implemented here, and this partial implementation enables it to work without warning about these methods being unimplemented.

That midlet also calls *stop*, which still warns about being unimplemented. And that's a bit strange, since it never actually calls any of the methods that would start an animation: *drag*, *kineticScroll*, and *limitedKineticScroll*.

But in any case, this partial implementation should behave the way the midlet expects. It's based on [these FrameAnimator docs](http://developer.nokia.com/resources/library/Java/_zip/GUID-237420DE-CCBE-4A74-A129-572E0708D428/com/nokia/mid/ui/frameanimator/FrameAnimator.html).