/// <summary>
        /// Copy a layerage ( form Layerbase to Clipboard).
        /// </summary>
        /// <param name="layerage"> The layerage. </param>
        public static void CopyLayerage(Layerage layerage)
        {
            //
            ILayer layer  = layerage.Self;
            ILayer clone2 = layer.Clone();

            Clipboard.Instances.Add(clone2);
            //

            LayerManager.CopyLayeragesCore(layerage.Children);
        }
        private static void CopyLayeragesCore(IList <Layerage> children)
        {
            foreach (Layerage layerage in children)
            {
                LayerManager.CopyLayeragesCore(layerage.Children);

                //
                ILayer layer = layerage.Self;
                ILayer clone = layer.Clone();
                Clipboard.Instances.Add(clone);
                //
            }
        }