vnstat: 1.14 -> 1.15 & add longDescription

Changes:
- Fix: XML output had extra commas, broken since previous version
- Fix: unintended shared pointer modification in mosecs() sometimes resulted
  in wrong month name to be shown for the current month
- Fix: possible buffer overflow in /proc/net/dev parsing, requires corrupted
  content in /proc/net/dev or use of address sanitizer
- Use ANSI escape codes in -l and -tr modes for cursor location manipulation
  instead of printing backspaces, hide cursor while output is active
- Improve database import robustness
- Improve support for Asian UTF-8 date strings
- Replace hand written Makefiles with Autotools
- Add --alwaysadd parameter to daemon for allowing automatic addition of
  interfaces even if the database directory was populated during startup

pkgs/applications/networking/vnstat/default.nix

@@ -1,29 +1,32 @@
-{stdenv, fetchurl, ncurses}:
+{ stdenv, fetchurl, ncurses }:
 
-let version = "1.14"; in
+let version = "1.15"; in
 stdenv.mkDerivation rec {
   name = "vnstat-${version}";
 
   src = fetchurl {
-    sha256 = "11l39qqv5pgli9zzn0xilld67bi5qzxymsn97m4r022xv13jlipq";
+    sha256 = "0fdw3nbrfm4acv48r0934ls6ld5lwkff3gyym2c72qlbm9dlp0f3";
     url = "http://humdi.net/vnstat/${name}.tar.gz";
   };
 
-  installPhase = ''
-    mkdir -p $out/{bin,sbin} $out/share/man/{man1,man5}
-    cp src/vnstat $out/bin
-    cp src/vnstatd $out/sbin
-    cp man/vnstat.1 man/vnstatd.1 $out/share/man/man1
-    cp man/vnstat.conf.5 $out/share/man/man5
-  '';
+  buildInputs = [ ncurses ];
 
-  buildInputs = [ncurses];
+  postPatch = ''
+    substituteInPlace src/cfg.c --replace /usr/local $out
+  '';
 
   meta = with stdenv.lib; {
     inherit version;
+    description = "Console-based network statistics utility for Linux";
+    longDescription = ''
+      vnStat is a console-based network traffic monitor for Linux and BSD that
+      keeps a log of network traffic for the selected interface(s). It uses the
+      network interface statistics provided by the kernel as information source.
+      This means that vnStat won't actually be sniffing any traffic and also
+      ensures light use of system resources.
+    '';
     homepage = http://humdi.net/vnstat/;
     license = licenses.gpl2Plus;
-    description = "Console-based network statistics utility for Linux";
     maintainers = with maintainers; [ nckx ];
     platforms = platforms.linux;
   };