Migrated AirLocate to unified api

- Changed int to nint being used as method parameter
- Changed NavigationController.PopViewControllerAnimated to
.PopViewController
- Changed new PointF to new CGPoint
- Changed new RectangleF to new CGRect
- Changed NSAction in DispatchQueue.DefaultGlobalQueue.DispatchAsync to
Action
- Changed NSAction in NSTimer.CreateTimer to Action<NSTimer>
- Changed parameter in overriden method from int to nint
- Changed return type of overridden method from int to nint
- Changed UIApplication.SharedApplication.PresentLocationNotificationNow
to .PresentLocalNotificationNow