Hide line handle
Hide line handle

In out case, we only need the handle to compute the bone translation
correctly. In VTK (vtkPointHandleRepresentation3D) the handle visibility
is turned on when ComputeInteractionState() is called.
So in order to have an invisible handle, the hack is to set it to a size
zero.

See Issue #13695

ricortiz/Bender,vovythevov/Bender,finetjul/bender,ricortiz/BenderCraniosynostosis,ricortiz/BenderCraniosynostosis,finetjul/bender,ricortiz/Bender,ricortiz/Bender,ricortiz/BenderCraniosynostosis,ricortiz/Bender,vovythevov/Bender,finetjul/bender,finetjul/bender,ricortiz/BenderCraniosynostosis,vovythevov/Bender,vovythevov/Bender