public class TreeEnsembleModel.SaveLoadV1_0$.EnsembleNodeData
implements scala.Product, scala.Serializable
Model data for model import/export.
We have to duplicate NodeData here since Spark SQL does not yet support extracting subfields
of nested fields; once that is possible, we can use something like:
case class EnsembleNodeData(treeId: Int, node: NodeData),
where NodeData is from DecisionTreeModel.