Locked frame times; SAM, GUN, AGUN work again.

- all frames are 40ms long. (except something in the sidebar, which should really be PlayFetchIndex anyway)
    - SAM, GUN, and AGUN no longer crash the game when built. (Turreted used Mobile, which those buildings don't have)

OpenRa.Game/Traits/Building.cs

@@ -12,7 +12,7 @@ namespace OpenRa.Game.Traits
 		}
 
 		bool first = true;
-		public void Tick(Actor self, Game game, int dt)
+		public void Tick(Actor self, Game game)
 		{
 			if (first && self.Owner == game.LocalPlayer)
 			{