Clean up some Widget properties.

Index: frontend/framework/source/class/qx/ui/table/Table.js
===================================================================
--- frontend/framework/source/class/qx/ui/table/Table.js	(revision 8461)
+++ frontend/framework/source/class/qx/ui/table/Table.js	(working copy)
@@ -1769,6 +1769,7 @@
   destruct : function()
   {
     this._cleanUpMetaColumns(0);
-    this._disposeObjects("_selectionManager", "_columnVisibilityMenu", "_tableModel", "_columnVisibilityBt", "_scrollerParent", "_statusBar");
+    this._disposeObjects("_selectionManager", "_columnVisibilityMenu",  "_columnVisibilityBt", "_scrollerParent", "_statusBar");
+    this._disposeProperties("tableModel", "selectionModel", "tableColumnModel", "dataRowRenderer");
   }
 });
Index: frontend/framework/source/class/qx/ui/table/pane/Scroller.js
===================================================================
--- frontend/framework/source/class/qx/ui/table/pane/Scroller.js	(revision 8461)
+++ frontend/framework/source/class/qx/ui/table/pane/Scroller.js	(working copy)
@@ -1985,5 +1985,7 @@
     this._disposeObjects("_verScrollBar", "_horScrollBar", "_header", "_headerClipper",
       "_spacer", "_top", "_tablePane", "_paneClipper", "_resizeLine", "_table",
       "_focusIndicator", "_topRightWidget");
+
+    this._disposeProperties("tablePaneModel");
   }
 });