Add key handling to order generators.

OpenRA.Game/Orders/IOrderGenerator.cs

@@ -22,5 +22,6 @@ namespace OpenRA
 		IEnumerable<IRenderable> RenderAboveShroud(WorldRenderer wr, World world);
 		string GetCursor(World world, CPos cell, int2 worldPixel, MouseInput mi);
 		void Deactivate();
+		bool HandleKeyPress(KeyInput e);
 	}
 }

OpenRA.Game/Orders/UnitOrderGenerator.cs

@@ -86,6 +86,8 @@ namespace OpenRA.Orders
 
 		public void Deactivate() { }
 
+		bool IOrderGenerator.HandleKeyPress(KeyInput e) { return false; }
+
 		// Used for classic mouse orders, determines whether or not action at xy is move or select
 		public virtual bool InputOverridesSelection(WorldRenderer wr, World world, int2 xy, MouseInput mi)
 		{