I enhanced the VTK to VTKm conversion. It now handles unstructured grids
with any cell type, skipping any unsupported types. Currently it skips
everything but hexahedra, since that is all the MarchingCubes worklet
handles. The code to not skip finite element zoo elements is currently 
commented out. The conversion also handles double coordinate arrays for 
unstructured grids and doubles for fields on any type of mesh. I haven't
enhanced anything else to handle doubles so having doubles will cause
things to crash.



git-svn-id: http://visit.ilight.com/svn/visit/trunk/src@27957 18c085ea-50e0-402c-830e-de6fd14e8384