add note in legacymapimporter about colorramp bitrot

OpenRA.Editor/LegacyMapImporter.cs

@@ -10,14 +10,13 @@
 
 using System;
 using System.Collections.Generic;
+using System.Drawing;
+using System.Globalization;
 using System.IO;
 using System.Linq;
 using System.Text;
-using OpenRA;
 using OpenRA.FileFormats;
 using OpenRA.Traits;
-using System.Drawing;
-using System.Globalization;
 
 namespace OpenRA.Editor
 {
@@ -83,6 +82,7 @@ namespace OpenRA.Editor
 //			{"scrate","crate"},
 		};
 		
+		// todo: fix this -- will have bitrotted pretty badly.
 		static Dictionary<string,Pair<Color,Color>> namedColorMapping = new Dictionary<string, Pair<Color, Color>>()
 		{
 			{"gold",Pair.New(Color.FromArgb(246,214,121),Color.FromArgb(40,32,8))},