IO/Xdmf3/Testing: Updated VToXLoop.py to new API.
IO/Xdmf3/Testing: Updated VToXLoop.py to new API.

keithroe/vtkoptix,sumedhasingla/VTK,SimVascular/VTK,keithroe/vtkoptix,sumedhasingla/VTK,keithroe/vtkoptix,SimVascular/VTK,SimVascular/VTK,sumedhasingla/VTK,keithroe/vtkoptix,SimVascular/VTK,sumedhasingla/VTK,SimVascular/VTK,SimVascular/VTK,keithroe/vtkoptix,keithroe/vtkoptix,sumedhasingla/VTK,SimVascular/VTK,SimVascular/VTK,keithroe/vtkoptix,keithroe/vtkoptix,sumedhasingla/VTK,sumedhasingla/VTK,sumedhasingla/VTK