[NOT READY TO MERGE] Animated List View

[thekevinbrown]

This is an attempt to port the work from @brentvatne with using the native list view scroll handler to make the animations smoother.

Unfortunately I'm still getting an error on scroll:

undefined is not an object (evaluating 'recEvt[mappingKey]') in traverse (AnimatedImplementation.js:2222:52).

I wanted to create this PR in case someone has experience getting the native scroll driver to work and knows how to fix this.

[thekevinbrown]

Working example: https://sketch.expo.io/B1v5RS7ix