xmlRemoveDefaultNamespace

A node extracted from a source document will inherit the default namespace of that document and carry it to the target. 

It's convenient to be able to remove the default namespace from the node before copying, e.g. when extracting the `<iq/>` node here

    <body xmlns="http://jabber.org/protocol/httpbind" 
            xmlns:stream="http://etherx.jabber.org/streams" 
            to="127.0.0.1" 
            rid="3" 
            sid="0acad5262d995374">
      <iq id="2" type="get" from="">
        <query xmlns="jabber:iq:auth">
          <username>xyz</username>
        </query>
      </iq>
    </body>