nss-mdns: fix version number format, general cleanup

stdenv.mkDerivation rec {

  pname = "nss-mdns";

  version = "v0.15.1";

  version = "0.15.1";

  src = fetchFromGitHub {

    owner = "lathiat";

    repo = pname;

    rev = version;

    repo = "nss-mdns";

    rev = "v${version}";

    hash = "sha256-iRaf9/gu9VkGi1VbGpxvC5q+0M8ivezCz/oAKEg5V1M=";

  };

  nativeBuildInputs = [ autoreconfHook pkg-config ];

  # Note: Although `nss-mdns' works by talking to `avahi-daemon', it

  # doesn't depend on the Avahi libraries.  Instead, it contains

  # hand-written D-Bus code to talk to the Avahi daemon.

  configureFlags =

    [ # Try to use the Avahi daemon before resolving on our own.

  configureFlags = [

    # Try to use the Avahi daemon before resolving on our own.

    "--enable-avahi"

    # Connect to the daemon at `/var/run/avahi-daemon/socket'.

    "--localstatedir=/var"

  ];

      resolution by common Unix/Linux programs in the ad-hoc mDNS

      domain `.local'.

    '';

    homepage = "http://0pointer.de/lennart/projects/nss-mdns/";

    license = lib.licenses.lgpl2Plus;

    # Supports both the GNU and FreeBSD NSS.

    platforms = lib.platforms.gnu ++ lib.platforms.linux ++ lib.platforms.freebsd;

    maintainers = [ ];

  };

}