[docs] xmldocs output formats

[Davor Ocelic]

I was looking a bit into the future just now, and I tried creating
.pdf documents out of our .xml files.

The whole thing looks *very* nice and promising; I provide
a link to a 'screenshot' which is itself fantastic-looking,
given that I generated it completely ad-hoc.

There are few things that stand out, but as I said, this
is without any customization layer, I directly ran the
vanilla docbook converter on it; if it looked halfway good,
I'd still think it was a success.

http://colt.projectgamma.com/tmp/pdf.preview.png

Enjoy!