Callback improvements suggestions

[rafaellop]

Improvement: Would be great to have callback information about user interaction. If he/she submitted a review or choosed "Canel" or "Not now". This could be useful to stop asking for a review again and again if it is already given. Also the callbacks on iOS <10.3 should return something e.g. a failure. At the moment they both return nothing. Would be useful to avoid checking iOS version (device.version) before calling the review dialog in the plugin.