deletion of allocation connections

...s/tooling/base/ui/editor/AllocationDiagramEditorBase.java

...rtiss/tooling/base/ui/editor/CommonDiagramEditorBase.java

...org/fortiss/tooling/base/ui/editor/DiagramEditorBase.java

...ui/editpart/allocation/AllocationDiagramEditPartBase.java

...ui/editpart/allocation/AllocationElementEditPartBase.java

...tpart/allocation/AllocationFreeConnectorEditPartBase.java

...art/allocation/AllocationStickyConnectorEditPartBase.java

...editpart/allocation/AllocationSubDiagramEditPartBase.java