Committed incomplete XML expat parser wrapper

I have committed the *incomplete* expat XML parser wrapper code to CVS -
as usual you can get it from

	http://www.w3.org/Library/cvs.html#update

and a description is at

	http://db.w3.org/Library/latest.sql

This will not affect you if don't explicitly enable it - hence doing CVS
updates is still safe.

If you want to play with it (finishing it) then you can enable it by
running configure with the --with-expat option. It doesn't look like
expat easily can be made into a library so if you have trouble linking
it then you can put it into the libwww source folder.

Henrik