Remove debug code.

src/Perspex.Controls/ItemsControl.cs

@@ -156,8 +156,6 @@ namespace Perspex.Controls
         /// <param name="e">The event args.</param>
         protected virtual void ItemsChanged(PerspexPropertyChangedEventArgs e)
         {
-            System.Diagnostics.Debug.WriteLine($"{this.GetType().Name} set items");
-
             var incc = e.OldValue as INotifyCollectionChanged;
 
             if (incc != null)

src/Perspex.Controls/Primitives/SelectingItemsControl.cs

@@ -295,8 +295,6 @@ namespace Perspex.Controls.Primitives
         /// <param name="e">The event args.</param>
         private void SelectedIndexChanged(PerspexPropertyChangedEventArgs e)
         {
-            System.Diagnostics.Debug.WriteLine($"{this.GetType().Name} set selected index");
-
             var index = (int)e.OldValue;
 
             if (index != -1)