bibtool: 2.57 -> 2.67

pkgs/tools/misc/bibtool/default.nix

···
 
 stdenv.mkDerivation rec {
   name = "bibtool-${version}";
-  version = "2.57";
+  version = "2.67";
 
   src = fetchurl {
     url = "http://www.gerd-neugebauer.de/software/TeX/BibTool/BibTool-${version}.tar.gz";
-    sha256 = "1g3yqywnbg04imkcqx7ypq0din81vcgq90k2xlqih69blbqpfb5y";
+    sha256 = "116pv532mz0q954y5b7c6zipnamc05f0x7g5x1b674jsjxh42v2v";
   };
 
   # Perl for running test suite.
···
   meta = with stdenv.lib; {
     description = "Tool for manipulating BibTeX bibliographies";
     homepage = http://www.gerd-neugebauer.de/software/TeX/BibTool/index.en.html;
-    license = licenses.gpl1;
+    license = licenses.gpl2;
     platforms = platforms.all;
     maintainers = [ maintainers.rycee ];
   };