I converted all the vtk classes that inherit from vtkDataSetToUnstructuredGridFilter 
to inherit from vtkUnstructuredGridAlgorithm, since vtkDataSetToUnstructuredGridFilter
is deprecated and isn't in VTK6.



git-svn-id: http://visit.ilight.com/svn/visit/trunk/src@20161 18c085ea-50e0-402c-830e-de6fd14e8384