add_text (REXML::Element)

    # File src/rexml/element.rb, line 482
                    def add_text( text )
                            if text.kind_of? String
                                    if @children[-1].kind_of? Text
                                            @children[-1] << text
                                            return
                                    end
                                    text = Text.new( text, whitespace(), nil, raw() )
                            end
                            self << text unless text.nil?
                            return self
                    end