Move solution and projects to src

src/Ryujinx.Ui.Common/App/ApplicationCountUpdatedEventArgs.cs

@@ -0,0 +1,10 @@
+using System;
+
+namespace Ryujinx.Ui.App.Common
+{
+    public class ApplicationCountUpdatedEventArgs : EventArgs
+    {
+        public int NumAppsFound  { get; set; }
+        public int NumAppsLoaded { get; set; }
+    }
+}