AddonLifecycle ReceiveEvent improvements (#1511)

* Prototype

* Add hook null safety

Add a check to make sure addons that invoke virtual functions for other addons don't trigger lifecycle messages multiple times.

* Expose event listeners for AddonLifecycleWidget.cs

Disable hook when all listeners for an addon unregister

* Add AddonLifecycleWidget.cs

* Remove excess logging

Dalamud/Interface/Internal/Windows/Data/DataWindow.cs

@@ -50,6 +50,7 @@ internal class DataWindow : Window
         new DataShareWidget(),
         new NetworkMonitorWidget(),
         new IconBrowserWidget(),
+        new AddonLifecycleWidget(),
     };
 
     private readonly IOrderedEnumerable<IDataWindowWidget> orderedModules;