move global defaults to a trait (half done)

OpenRA.Game/Traits/World/Shroud.cs

@@ -1,4 +1,4 @@
-#region Copyright & License Information
+#region Copyright & License Information
 /*
  * Copyright 2007,2009,2010 Chris Forbes, Robert Pepperell, Matthew Bowra-Dean, Paul Chote, Alli Witheford.
  * This file is part of OpenRA.
@@ -29,6 +29,7 @@ namespace OpenRA.Traits
 {
 	public class ShroudInfo : ITraitInfo
 	{
+		public readonly int ShroudRate = 0;
 		public object Create(Actor self) { return new Shroud(self, this); }
 	}