export the Animated and AnimatedWithChildren base classes?

[gre]

I'm only starting to implement my own Animated class for my own requirements (animated over OpenGL uniforms), however the Animated class (used to define most of animated* classes) is not exposed.

Exposing it would allow to have more third party libs: (1) that can create there own animated more easily and also (2) that can do things like foo instanceof Animated instead of ducktyping.

That said i'm not sure if all the methods aim to be "final", I mean __getValue, __getAnimatedValue, __addChild, ...
But when it's "finalized", it would be great to have a small doc to explain concepts of __getValue and __getChildren (i'm still new to Animated implementation, the lib design is still mindblowing to me, I really like how things are reversed from "classical" animation libs (the fact that spring function drives the animation in a "bottom-up" way, instead of letting the value flow top-down like in react-motion ) ).