add vmpk 0.5.1, a virtual midi piano keyboard

pkgs/applications/audio/vmpk/default.nix

@@ -0,0 +1,26 @@
+{ stdenv, fetchurl, cmake, pkgconfig
+, qt4, jackaudio
+}:
+
+let
+  version = "0.5.1";
+in stdenv.mkDerivation rec {
+  name = "vmpk-${version}";
+
+  meta = with stdenv.lib; {
+    description = "Virtual MIDI Piano Keyboard";
+    homepage    = "http://vmpk.sourceforge.net/";
+    license     = licenses.gpl3Plus;
+    platforms   = platforms.linux;
+    maintainers = with maintainers; [ iyzsong ];
+  };
+
+  src = fetchurl {
+    url = "mirror://sourceforge/vmpk/${version}/${name}.tar.bz2";
+    sha256 = "11fqnxgs9hr9255d93n7lazxzjwn8jpmn23nywdksh0pb1ffvfrc";
+  };
+
+  nativeBuildInputs = [ cmake pkgconfig ];
+
+  buildInputs = [ qt4 jackaudio ];
+}

pkgs/top-level/all-packages.nix

@@ -9163,6 +9163,8 @@ let
 
   vlc = callPackage ../applications/video/vlc { };
 
+  vmpk = callPackage ../applications/audio/vmpk { };
+
   vnstat = callPackage ../applications/networking/vnstat { };
 
   vorbisTools = callPackage ../applications/audio/vorbis-tools { };