Implementation of see-also idea by Fredrik Lundh.

See http://effbot.org/zone/idea-seealso.htm for the XML description.

parse-seealso.py : retrieves a URL, parses contents, adds them to a 
		   pickled dictionary
		   
make-seealso.py : reads the dictionary and outputs *.tex files

Error trapping is minimal; usually it'll die with an exception 
if something goes wrong.

--amk