Adding installation of manpage in debian.

* Add sphinx support via setup.py. Try it! e.g.
  $ python setup.py build_sphinx -b man
* Add installation of manpage in debian/rules
* Use mkdir -p to create dirs in debian/rules
Remove useless [upload_sphinx] section in setup.cfg.

(My apologies for the mess)
Add python-twisted as Build-Dependency in order to run trial.