features.add(new ElementDepthFeature());
features.add(new ItemNumberInParentFeature());
features.add(new NumberOfChildrenFeature());
features.add(new NumberOfDescendentsFeature());
features.add(new IsTheOnlyChildFeature());
features.add(new ChildrenDepthFeature());
features.add(new SectionDepthFeature());
features.add(new NumberOfSiblingsFeature());
features.add(new NumberOfSiblingsSameTypeFeature());
}