Used identifiers rather than paths to find the print and HTML stylesheets.
N.B. This means that building docs won't work unless you set
SGML_CATALOG_FILES to
/usr/lib/sgml/CATALOG:/usr/lib/sgml/stylesheets/nwalsh-modular/docbook.cat,
or wait for this lot to be added to the build system (RSN).

Changed default text size to "normal".

Changed default paper size for SGML output to A4 (%paper-type%).

Stylesheet used for processing SGML. Initially it's identical to the Cygnus
DocBook Tools stylesheet, with %section-autonumber% set to true for HTML, so
that all sections are numbered.