def add_element name, value = nil
      value = value.respond_to?(:xmlschema) ? value.xmlschema : value.to_s
      XML.new super(name, value)
    end
def add_element name, value = nil
      value = value.respond_to?(:xmlschema) ? value.xmlschema : value.to_s
      XML.new super(name, value)
    end
Adds an element to the root.