move gzip and gunzip in a seperate directory to avoid having the hash encoded in the binary name

svn path=/nixpkgs/trunk/; revision=1580

pkgs/stdenv/nix-linux-static/gzip-static/builder.sh

@@ -1,5 +1,5 @@
 . $stdenv/setup
  
 mkdir $out
-cp -a $src1 $out
-cp -a $src2 $out
+cp -a gzip $out/bin
+cp -a gunzip $out/bin

pkgs/stdenv/nix-linux-static/gzip-static/default.nix

@@ -3,6 +3,4 @@
 stdenv.mkDerivation {
   name = "gzip-static-1.3.3";
   builder = ./builder.sh;
-  src1 = ./gzip;
-  src2 = ./gunzip;
 }