Support custom Spring Configurations

## Describe the feature

I believe the native `UIPageViewController` supports custom spring configurations, so it would be nice to expose those to React Native. In my case, I want the spring animation a lot stiffer as it is currently a bit slow. It would be awesome to be able to configure this via the React component.

Another solution would be to simply expose the `x` value, which you can then animate using Reanimated - this requires little changes for this library and provides unlimited extensibility as we can now animate the `x` value as we wish (`Reanimated.createAnimatedComponent(PagerView)` then assign `x` to a `SharedValue`)

## Motivation

* More customizability

## Related Issues