Treewide: use HTTPS on GNU domains

HTTP -> HTTPS for :
- http://gnu.org/
- http://www.gnu.org/
- http://elpa.gnu.org/
- http://lists.gnu.org/
- http://gcc.gnu.org/
- http://ftp.gnu.org/ (except in fetchurl mirrors)
- http://bugs.gnu.org/

pkgs/development/libraries/vcdimager/default.nix

@@ -17,7 +17,7 @@ stdenv.mkDerivation rec {
   propagatedBuildInputs = [ libcdio ];
 
   meta = with lib; {
-    homepage = http://www.gnu.org/software/vcdimager/;
+    homepage = https://www.gnu.org/software/vcdimager/;
     description = "Full-featured mastering suite for authoring, disassembling and analyzing Video CDs and Super Video CDs";
     platforms = platforms.unix;
     license = licenses.gpl2;