Add overload for a Promise's Reject method to allow objects/JObject to be sent

[henningms]

In some instances it would be nice to be able to pass along a custom error object in the Reject method for a Promise/IPromise.

[rozele]

@henningms we're just following the lead of what other platforms support for reject (e.g., there is no reject-with-error-object here https://github.com/facebook/react-native/blob/master/ReactAndroid/src/main/java/com/facebook/react/bridge/Promise.java). You could, in the meantime, "resolve" the promise with the object and then trigger the error path from JavaScript.

[rozele]

We could do something like this https://github.com/facebook/react-native/blob/d368ebfab2c389cc093f6a73e5c1021408cc6a73/React/Base/RCTUtils.m#L410, which shows how iOS adds a couple extra fields to the JS error object from the NSError, but it doesn't look like it supports and arbitrary custom error object.

[rozele]

Scratch that last statement, the above link shows how iOS uses the NSError userInfo field (which generally is a dictionary) to support custom fields. I'll look and see how we can support something similar and how/if it's done on Android.

[rozele]

Looks like it's not supported on Android (probably because Java Throwables do not have the concept of 'userInfo' that's used on iOS). https://github.com/facebook/react-native/blob/master/ReactAndroid/src/main/java/com/facebook/react/bridge/PromiseImpl.java#L58