Fixed bug #828: Docs in PDF. There was already a rule for making

pazpar2.pdf using jade + pdfjadetex, but there was some constructs in
the documentation that jade considered invalid. So it did not succeed.
And indeed jade is right in a number of cases, where xsltproc does not
validate. However, jade does NOT currently allow references to refsect1,
refsect2.. sections which makes it impossible to refer to stuff from the
Guide to the Reference material. This is major drawback so dblatex is used
instead. dblatex, like jadetex, makes PDF/tex from Docbook. dblatex allows
these references and dblatex is more actively developed and is available
as a Debian package for sarge. Run 'make pazpar2.pdf' to make the
documentation. There is also a 'jade-check' rule.