Description of problem:
Splitter is a very handy tool for generating program listings in
documentation, but it doesn't work well for XML "programs". Two
reasons for that:
1. "<!-- @rhdoc.begin foo.sgml -->" does not work because the trailing
"-->" is not stripped away.
2. XML documents do not allow comments preceeding the <?xml?>
declaration or otherwise outside the root element. If you want to
insert an entire XML document as an example listing, you will not be
able to bracket it with XML comments and still have working code.