Patch to readd documentation

The attached patch adds the old JDBC documentation, which was lost
during the move. Along the way I've converted it to XML so it is more
easily possible to use Java-based XSLT processors in it, which probably
goes over better around here.

To build it, use:

ant -Ddocbook.stylesheet='/some/where/xhtml/chunk.xsl' doc

You can download the stylesheets here:

http://sourceforge.net/project/showfiles.php?group_id=21935&package_id=16608

(Eventually, we should support fetching them directly over http and/or
support XML catalogs.)

You might need to use JDK 1.4 or install additional classes, according
to the Ant documentation.

If the build process crashes with an error message like this:

.../gentext.xsl:230:57: Error! Variable accessed before it is bound!

you should try to use Saxon to do the transformation. I have done the
following:

export CLASSPATH=/usr/share/saxon-6.5.2/saxon.jar:$CLASSPATH

The HTML rendition will end up in build/doc.

The content of the documentation could probably be overhauled as well,
but I just focused on integrating the existing material before it's
forgotten.