Debian packaging cleanup

* Use cleaner rules file from the official Debian package,
  by Ritesh Raj Sarraf <rrs@debian.org> (Thanks!)
* Got rid of explicit handling of python versions
* Let go of all the pre/post inst/rm scripts
* Copyright file cleanup
* Updated author's email address and project homepage
Updated copyright notices to 2014
Replaced README by README.md

* Rewrote the contents to be provide more information
* Using Markdown for better integration with Github