Add article, code, toc, and redirects (#1343)

dotnet-desktop-guide/net/wpf/events/snippets/object-lifetime-events/csharp/App.xaml.cs

@@ -0,0 +1,11 @@
+using System.Windows;
+
+namespace CodeSampleCsharp
+{
+    /// <summary>
+    /// Interaction logic for App.xaml
+    /// </summary>
+    public partial class App : Application
+    {
+    }
+}