SceneObject now defaults to a category of "misc"
getCategoryOfClass now checks parent classes for what categories they hold so that variants can inherit
categories are in one of a few rough groups and subgroups depending on actual mapper needs/usages
-Added: SkySphere a full sphere skyBox
-Change: ScatterSky now renders a dome instead of the top face of a cubeSphere
-Change: Creator now has skySphere
TODO: Simplify sphere creation
PossibleMethod: Add the sphere creation functions to one place to be shared around.