TODO list:
* Make more passes over the documentation
* More demo programs 
* Lots of docstrings!
        * Re-indent everything to 4-space indents
* Flesh out the test suite more

demo/xbel/
* Update all the software to match the current XBEL DTD
* Add a test suite for the basic parser

dom/
* Element.removeAttributeNode needs to know about DTDs to
restore a default value.

* Greg Stein owes doc on qp_xml