Instantiate local notifications different than remote notifications

Summary:
To use `PushNotificationIOS` for local notifications in the same way as we use them for remote notifications. Today remote notifications are being constructed correctly but local notifications are not. Related issue: https://github.com/facebook/react-native/issues/8014

When ObjC receives local notifications it does not serialize the `UILocalNotification` the same way as we do for remote notifications. And when we go to construct a `PushNotificationIOS` javascript instance it works for remote notifications but not for local notifications.

- Some of remote notification's data is wrapped in an `aps` dict (https://developer.apple.com/library/ios/documentation/NetworkingInternet/Conceptual/RemoteNotificationsPG/Chapters/TheNotificationPayload.html#//apple_ref/doc/uid/TP40008194-CH107-SW1).
- All of local notifications are being received and passed to javascript as a flat dictionary: (https://github.com/facebook/react-native/blob/maste
Closes https://github.com/facebook/react-native/pull/8029

Differential Revision: D3417260

Pulled By: javache

fbshipit-source-id: c130aa39e89ffbbd8b1243b6dacbf95bb591b4da