Improved documentation and more configuration attributes

Thanks for this module. It still took my some hours to get it working for my application because I was not used to create Debian packages and because "the following assumptions" from this module did not fully match. With with patch it might be easier for the next one and one can configure more freely. By the way I don't use perlbew but carton, so the assumption `XXX perlbrew` might also be removed.

By the way, can one automatically call `dpkg-buildpackage` with this plugin? Right now I need to `dzil build && cd My-Package-XX && cd .. && dpkg-buildpackage` to do so.