Unify ra and cnc main menu logic and clean up the main menus.

Move a bunch of buttons into an Extras submenu and the server browser.
Move CncMenuPaletteEffect to ra so it can be used elsewhere and rename it to MenuPaletteEffect.

OpenRA.Mods.Cnc/Widgets/Logic/CncMainMenuLogic.cs

@@ -0,0 +1,30 @@
+#region Copyright & License Information
+/*
+ * Copyright 2007-2014 The OpenRA Developers (see AUTHORS)
+ * This file is part of OpenRA, which is free software. It is made
+ * available to you under the terms of the GNU General Public License
+ * as published by the Free Software Foundation. For more information,
+ * see COPYING.
+ */
+#endregion
+
+using OpenRA.Mods.RA.Widgets.Logic;
+using OpenRA.Widgets;
+
+namespace OpenRA.Mods.Cnc.Widgets.Logic
+{
+	public class CncMainMenuLogic : MainMenuLogic
+	{
+		[ObjectCreator.UseCtor]
+		public CncMainMenuLogic(Widget widget, World world)
+			: base(widget, world)
+		{
+			var shellmapDecorations = widget.Get("SHELLMAP_DECORATIONS");
+			shellmapDecorations.IsVisible = () => menuType != MenuType.None && Game.Settings.Game.ShowShellmap;
+			shellmapDecorations.Get<ImageWidget>("RECBLOCK").IsVisible = () => world.FrameNumber / 25 % 2 == 0;
+
+			var shellmapDisabledDecorations = widget.Get("SHELLMAP_DISABLED_DECORATIONS");
+			shellmapDisabledDecorations.IsVisible = () => !Game.Settings.Game.ShowShellmap;
+		}
+	}
+}