split remap classes

OpenRa.FileFormats/SingleColorRemap.cs

@@ -0,0 +1,18 @@
+using System.Drawing;
+
+namespace OpenRa.FileFormats
+{
+	public class SingleColorRemap : IPaletteRemap
+	{
+		Color c;
+		public SingleColorRemap(Color c)
+		{
+			this.c = c;
+		}
+
+		public Color GetRemappedColor(Color original, int index)
+		{
+			return original.A > 0 ? c : original;
+		}
+	}
+}