obsoleting legacy prop eds

src/umbraco.editorControls/MultiNodeTreePicker/SelectedItemsTemplate.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Web;
 using System.Web.UI;
 using System.Web.UI.HtmlControls;
@@ -10,6 +11,7 @@ namespace umbraco.editorControls.MultiNodeTreePicker
     /// <summary>
     /// The item template for the selected items repeater
     /// </summary>
+    [Obsolete("IDataType and all other references to the legacy property editors are no longer used this will be removed from the codebase in future versions")]
     internal class SelectedItemsTemplate : ITemplate
     {
         #region ITemplate Members