remove DS lua library since it has no methods and no immediately plans to add any

BizHawk.Client.Common/lua/EmuLuaLibrary.DS.cs

@@ -1,25 +0,0 @@
-using System;
-using System.ComponentModel;
-using System.Drawing;
-using BizHawk.Emulation.Common;
-using BizHawk.Emulation.Cores.Consoles.Nintendo.NDS;
-using NLua;
-
-// ReSharper disable UnusedMember.Global
-namespace BizHawk.Client.Common.lua
-{
-	[Description("Functions specific to DSHawk (functions may not run when an NDS game is not loaded)")]
-	public sealed class DSLuaLibrary : DelegatingLuaLibrary
-	{
-		public DSLuaLibrary(Lua lua)
-			: base(lua) { }
-
-		public DSLuaLibrary(Lua lua, Action<string> logOutputCallback)
-			: base(lua, logOutputCallback) { }
-
-		public override string Name => "nds";
-
-		[RequiredService]
-		public IEmulator Emulator { get; set; }
-	}
-}