mrtg: add 2.17.4

- The Multi Router Traffic Grapher
- You have a router, you want to know what it does all day long?
- Then MRTG is for you. It will monitor SNMP network devices and draw
- pretty pictures showing how much traffic has passed through each interface.

pkgs/tools/misc/mrtg/default.nix

···
+{ stdenv, fetchurl, perl, gd, rrdtool }:
+
+stdenv.mkDerivation rec {
+
+  version = "2.17.4";
+  name = "mrtg-${version}";
+
+  src = fetchurl {
+    url = "http://oss.oetiker.ch/mrtg/pub/${name}.tar.gz";
+    sha256 = "0r93ipscfp7py0b1dcx65s58q7dlwndqhprf8w4945a0h2p7zyjy";
+  };
+
+  buildInputs = [
+    perl gd rrdtool
+  ];
+
+  meta = {
+    description = "The Multi Router Traffic Grapher";
+    homepage = http://oss.oetiker.ch/mrtg/;
+    license = stdenv.lib.licenses.gpl2;
+    maintainers = [ stdenv.lib.maintainers.robberer ];
+  }; 
+}

pkgs/top-level/all-packages.nix

···
 
   mr = callPackage ../applications/version-management/mr { };
 
+  mrtg = callPackage ../tools/misc/mrtg { };
+
   mscgen = callPackage ../tools/graphics/mscgen { };
 
   msf = builderDefsPackage (import ../tools/security/metasploit/3.1.nix) {