Add lighting, opacity, and scalar mapping
Add lighting, opacity, and scalar mapping

This adds in a few missing pieces to the contour state restoration, and
ensures that the dialog shows the values as set by the state file.

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