Add Typescript types and documentation for Promise Rejection

[mjaggard]

Introduction

When developing a React Native app which uses NativeModules I found myself wanting to handle errors but struggling to even know what types should be returned for rejection of promises.

Discussion points

1. I think documentation needs improvement for promise rejection, unless I missed something I couldn't find any info on that.
2. There should be some types provided for those using Typescript to deal with the result of a rejection.
   The type should have these properties for Android:
   https://github.com/facebook/react-native/blob/1ca63e3e3dff6639f4efde74583145f9fa53759a/packages/react-native/ReactAndroid/src/main/java/com/facebook/react/bridge/PromiseImpl.java#L31