Load NSUserDefaults from previous Android app.

We're porting one of our native Android games to Unity and want the new version to be an upgrade of the old one using the same package name and keystore. We really need to transfer the NSUserDefaults from the old native app to the new Unity one. Is there any way Unity can read NSUserDefaults? Some of the settings are saved as nested dictionaries so I'm guessing that just using PlayerPrefs won't do the trick.