feat: Android Camera v2 API

[dpa99c]

This PR contains a rewrite of the Android implementation to use the Camera v2 API instead of the deprecated Camera API.

The main reason for this change is to fix issues I was encountering with the existing implementation where the camera preview/captured image from this plugin did not correspond the camera preview/captured image from the default Camera app. i.e. this fixes #275

It also opens the way to fetch the device's camera details and select a specific camera/lens based on these [see #256]. While the fetch side is implemented by this PR (getCameraCharacteristics()), the selection of a specific camera/lens is not (as I didn't need it for my use case).

I also implements getZoom(), setZoom() and getMaxZoom() on both Android & iOS, reworking my previous PR #326 on Android to work with Camera v2 API.