public Iterator<Annotation> iteratorRecursive(SpanNode node) {
        return annotations.iteratorRecursive(node);
    }
Returns a recursive Iterator over all annotations that annotate the given node and its subnodes.

@param node the node to recursively return annotations for.
@return a recursive Iterator over all annotations that annotate the given node and its subnodes.
document/src/main/java/com/yahoo/document/annotation/SpanTree.java