gst-*: maintenance 1.8.1 -> 1.8.2

For now I left *-vaapi out, as the jump would be larger,
simple update isn't enough, and it's unreferenced in nixpkgs.

pkgs/development/libraries/gstreamer/core/default.nix

@@ -3,7 +3,7 @@
 }:
 
 stdenv.mkDerivation rec {
-  name = "gstreamer-1.8.1";
+  name = "gstreamer-1.8.2";
 
   meta = {
     description = "Open source multimedia framework";
@@ -15,7 +15,7 @@ stdenv.mkDerivation rec {
 
   src = fetchurl {
     url = "${meta.homepage}/src/gstreamer/${name}.tar.xz";
-    sha256 = "01ribrzc4x9xlv6ci66w2svpqxywjc129m6f2xy9gp82jgxj4dss";
+    sha256 = "9dbebe079c2ab2004ef7f2649fa317cabea1feb4fb5605c24d40744b90918341";
   };
 
   outputs = [ "dev" "out" ];