migrating most things to use the Target struct rather than Actor directly.

OpenRA.Mods.RA/AttackPlane.cs

@@ -23,7 +23,7 @@ namespace OpenRA.Mods.RA
 
 		protected override void QueueAttack(Actor self, Order order)
 		{
-			target = order.TargetActor;
+			target = Target.FromActor(order.TargetActor);
 			self.QueueActivity(new FlyAttack(order.TargetActor));
 		}
 	}