apcu: init at 4.0.7

closes #6334

pkgs/top-level/php-packages.nix

···
     inherit (pkgs) stdenv autoreconfHook fetchurl;
   };
 
+  apcu = buildPecl {
+    name = "apcu-4.0.7";
+
+    sha256 = "1mhbz56mbnq7dryf2d64l84lj3fpr5ilmg2424glans3wcg772hp";
+  };
+
   memcache = buildPecl {
     name = "memcache-3.0.8";