fixed Copy/Paste mechanism

...e/ui/dnd/gef/ConnectionCompositionDropTargetListener.java

...base/ui/dnd/gef/ElementCompositionDropTargetListener.java

...ase/ui/dnd/jface/ViewerElementCompositionDropAdapter.java

...rnel/ui/dnd/CompositionServiceLocalCopyPasteTransfer.java

...ing/kernel/ui/dnd/CompositionServiceLocalDNDTransfer.java

...kernel/ui/dnd/ConnectionCompositionDragSourceAdapter.java

...kernel/ui/dnd/ConnectionCompositionDropTargetAdapter.java

...ng/kernel/ui/dnd/ElementCompositionDragSourceAdapter.java

...ng/kernel/ui/dnd/ElementCompositionDropTargetAdapter.java

...rc/org/fortiss/tooling/kernel/ui/util/CopyPasteUtils.java

.../org/fortiss/tooling/kernel/ui/util/DragAndDropUtils.java

...rc/org/fortiss/tooling/kernel/ui/util/SelectionUtils.java