Update use of field association enumerations
The enumerations in `vtkm::cont::Field::Association` were renamed in the previous commit. The old names still exist, but are deprecated. Change the rest of the code to use the new names.
The enumerations in `vtkm::cont::Field::Association` were renamed in the previous commit. The old names still exist, but are deprecated. Change the rest of the code to use the new names.