Revert "Merge branch 'k3b' of git://github.com/ttuegel/nixpkgs"

It turns out this doesn't work due to setuid issues. I had been under
the impression that it was partially broken, but it is in fact totally
broken.

This reverts commit 718466074fa03de4dc1ab0d333fb43d8bbed2c8f, reversing
changes made to ea9c8d6a131502009ec583f1c7f785b511c36b8c.