Make makefile work with OS X (after installing docbook-bundle docbook-xsl and libxslt with fink on 10.3), cp has no -u flag on OSX (or solaris not sure about other BSDs)
changing to always create catalog backup file on export even if one already exists (not sure if this is necessarily the right thing to do, but at least it's what I seem to need most often)
Pulled out the call to get__path from the main query in 'folder-chunk' and added a separate query before that db_multirow - suggested by Dave and Don for scalability reasons.
