Add version attribute where maintainers |= nckx

This will probably be mandatory soon, and is a step in the right
direction. Removes the deprecated meta.version, and move some meta
sections to the end of the file where I should have put them in
the first place.

pkgs/games/soi/default.nix

@@ -1,9 +1,9 @@
 { stdenv, fetchurl, cmake
 , boost, eigen2, lua, luabind, mesa, SDL }:
 
-let version = "0.1.2"; in
 stdenv.mkDerivation rec {
   name = "soi-${version}";
+  version = "0.1.2";
 
   src = fetchurl {
     url = "mirror://sourceforge/project/soi/Spheres%20of%20Influence-${version}-Source.tar.bz2";