minecraft: fix wrapper

Adding jre lib path seems no longer needed, and so does padsp.

pkgs/games/minecraft/default.nix

···
 { stdenv, fetchurl, jre, libX11, libXext, libXcursor, libXrandr, libXxf86vm
-, mesa, openal, alsaOss, pulseaudioSupport ? false, libpulseaudio }:
+, mesa, openal
+, useAlsa ? false, alsaOss ? null }:
 
-assert jre ? architecture;
+assert useAlsa -> alsaOss != null;
 
 stdenv.mkDerivation {
-  name = "minecraft-2013.07.01";
+  name = "minecraft-2015.07.24";
 
   src = fetchurl {
     url = "https://s3.amazonaws.com/Minecraft.Download/launcher/Minecraft.jar";
···
     #!${stdenv.shell}
 
     # wrapper for minecraft
-    export LD_LIBRARY_PATH=\$LD_LIBRARY_PATH:${jre}/lib/${jre.architecture}/:${libX11}/lib/:${libXext}/lib/:${libXcursor}/lib/:${libXrandr}/lib/:${libXxf86vm}/lib/:${mesa}/lib/:${openal}/lib/
-    ${if pulseaudioSupport then "${libpulseaudio}/bin/padsp" else "${alsaOss}/bin/aoss" } \
+    export LD_LIBRARY_PATH=\$LD_LIBRARY_PATH:${libX11}/lib/:${libXext}/lib/:${libXcursor}/lib/:${libXrandr}/lib/:${libXxf86vm}/lib/:${mesa}/lib/:${openal}/lib/
+    ${if useAlsa then "${alsaOss}/bin/aoss" else "" } \
       ${jre}/bin/java -jar $out/minecraft.jar
     EOF
 

pkgs/top-level/all-packages.nix

···
   mfoc = callPackage ../tools/security/mfoc { };
 
   minecraft = callPackage ../games/minecraft {
-    pulseaudioSupport = config.pulseaudio or true;
+    useAlsa = config.minecraft.alsa or false;
   };
 
   minecraft-server = callPackage ../games/minecraft-server { };