CatalogueManager drivers for current v.w.o sgml-lib

I've just been through the entity catalogues and written out
a set of CatalogueManager drivers to recreate them.  Posting now
(possibly prematurely) so anyone interested has time to look
before this afternoon.  Matters arising: do we want to re-org
anything and/or expand the catalogue?

Some anomalies:

xml.soc has entries for PR-smil20-20010605, but that's missing in cvs
html 2 - I can't find URLs for them

also, how do the flat DTDs work?  Don't they lose flexibility to
declare an internal subset?

-- 
Nick Kew