Updated debian/ for protocol version 12

Updated debian/ to build current version, with updated version number. 
This would be considered greater than 0.12 by dpkg, but it isn't because cjdns 0.12 is not actually released, what we have here are development snapshots potentially leading up to 0.12. So you should use something like 0.12~patch1 instead.

However, I do not understand where the patch versions are coming from (and this might mean that the users will not either). Also, due to the rapid development cycle of cjdns I don't think that hardcoding patch versions here is any good; they would be outdated way too soon. I even had to make my repo build scripts read the major *protocol* revision from cjdns source code because it changed too often for me to keep up. Instead of manual patch revisions my repository at http://ubuntu.repo.cjdns.ca/ embeds the git commit identifier (part of the commit hash) in the version, as well as the total commit count to ensure that the version is always going up. Like this: "0.12.0+r3179+trusty1~gitf176d2c"