Refactor IPC services to have commands into separate classes, fix readme url

Ryujinx.Core/OsHle/IpcServices/Vi/ISystemDisplayService.cs

@@ -0,0 +1,25 @@
+using Ryujinx.Core.OsHle.Ipc;
+using System.Collections.Generic;
+
+namespace Ryujinx.Core.OsHle.IpcServices.Vi
+{
+    class ISystemDisplayService : IIpcService
+    {
+        private Dictionary<int, ServiceProcessRequest> m_Commands;
+
+        public IReadOnlyDictionary<int, ServiceProcessRequest> Commands => m_Commands;
+
+        public ISystemDisplayService()
+        {
+            m_Commands = new Dictionary<int, ServiceProcessRequest>()
+            {
+                { 2205, SetLayerZ }
+            };
+        }
+
+        public static long SetLayerZ(ServiceCtx Context)
+        {
+            return 0;
+        }
+    }
+}