Get Status Bar Height on iOS

[javasuns]

Fixes #243 Android Code Needs Implementation

[LordTylus]

Android Implementation could look like this:

        Resources resources = activity.getResources();

        int statusbarHeightResourceId = resources.getIdentifier("status_bar_height", "dimen", "android");

        if (statusbarHeightResourceId > 0)
            return resources.getDimensionPixelSize(statusBarHeightResourceId);

        return 0;