Add VTK type caster to convert VTK wrapped classes
Add VTK type caster to convert VTK wrapped classes

This type caster from SMTK manages converting VTK wrapped class into
the appropriate VTK class on the C++ side.

OpenChemistry/tomviz,OpenChemistry/tomviz,OpenChemistry/tomviz,mathturtle/tomviz,mathturtle/tomviz,OpenChemistry/tomviz,mathturtle/tomviz