Forbid copying and assignment in layout classes.

Specifically in:
 * BAbstractLayout
 * BAbstractLayoutItem
 * BGridLayout
 * BGridView
 * BGroupLayout
 * BGroupView
 * BLayout
 * BSplitView
 * BTwoDimensionalLayout

headers/os/interface/Layout.h

@@ -104,6 +104,10 @@ private:
 	virtual	void				_ReservedLayout9();
 	virtual	void				_ReservedLayout10();
 
+	// forbidden methods
+								BLayout(const BLayout&);
+			void				operator =(const BLayout&);
+
 			friend class BView;
 
 			void				SetOwner(BView* owner);