Support native events

## Describe the Feature

**Native Events** instead of ~js events~:
`onValueChange`
`onSlidingStart`
`onSlidingComplete`

## Possible Implementations

Supporting **native events** will unlock the abilities of `Animated.event` enabling tracking the Slider's value and animating stuff accordingly.
This will enable customizing this view to a large extent easily and with high performance.

Avoiding breaking changes can be achieved with a flag from props or by checking `typeof props.onValueChange === 'object'`

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### Android JS Impl
Uses `Slider` for `value` and renders the rest on top.
Native events will enhance this extremely and make *dev experience* easier (less code needed for customization)


## Related Issues

首先跟踪 issue 中描述的 Android JS 实现，尤其是 Slider 值变化和所列事件的连接方式。将当前的 JavaScript 事件与 React Native 的 native-event 处理进行比较，并确定 Animated.event 应如何接收 Slider 更新。完成标准是三个原生事件能够正常工作，同时不破坏现有的 JavaScript 事件用户。

由索引模型根据 Issue 内容生成。