celf: fix version, update license, remove name

pkgs/by-name/ce/celf/package.nix

@@ -5,10 +5,9 @@
   smlnj,
 }:
 
-stdenv.mkDerivation rec {
+stdenv.mkDerivation {
   pname = "celf";
-  pversion = "2013-07-25";
-  name = "celf-${pversion}";
+  version = "2.9.3-unstable-2013-07-25";
 
   src = fetchFromGitHub {
     owner = "clf";
@@ -35,7 +34,7 @@ stdenv.mkDerivation rec {
     description = "Linear logic programming system";
     mainProgram = "celf";
     homepage = "https://github.com/clf/celf";
-    license = lib.licenses.gpl3;
+    license = lib.licenses.gpl3Only;
     maintainers = with lib.maintainers; [ bcdarwin ];
     platforms = lib.platforms.unix;
   };