Localize 'No Camera Detected' and provide a 'notInitializedBuilder'

[martin-braun]

The text "No Camera Detected" is hardcoded. Maybe we could translate it to several languages.

Alternatively, or additionally, we could also add a notInitializedBuilder that allows the user to inject their own UI for when the permission has not been accepted or a camera cannot be found.

I tried to do this from outside the component, but the render will not re-trigger when this._controller.value.isInitialized flips