Persists a Window's Size, Location and WindowState to UserScopeSettings
 /// <summary>
 /// Called when Save is changed on an object.
 /// </summary>
 private static void OnSaveInvalidated(DependencyObject dependencyObject, DependencyPropertyChangedEventArgs e)
 {
     var window = dependencyObject as Window;
     if (window == null || !((bool) e.NewValue)) return;
     var settings = new WindowSettings(window);
     settings.Attach();
 }
 public WindowApplicationSettings(WindowSettings windowSettings)
     : base(windowSettings._window.GetType().FullName)
 {
 }