Packages that need util-linux-ng as a build-time or run-time dependency
typically refer to the attribute 'utillinux', which is the expression with
the least possible set of features.
Users, however, who run "nix-env -i util-linux", don't want that version,
because it lacks support for perl and curses. In other words, users want
utillinuxngCurses by default, which is what this change accomplishes.
svn path=/nixpkgs/trunk/; revision=27749
2eb4c12012