Package for the Polari IRC app

This commit includes a patch to telepathy's derivation, written by
Lethalman. This patch makes public the Telepathy's dependency to
dbus_glib. This patch will become problematic with the next pkgconfig
upgrade but this upgrade should make the patch irrelevant. See these 2
links for more information:
- https://bugs.freedesktop.org/show_bug.cgi?id=15199
- https://bugzilla.redhat.com/show_bug.cgi?id=436773

Modified by Luca Bruno:
- Moved telepathy_idle to propagatedUserEnvPkgs
- Added myself to maintainers
- Enable parallel building

pkgs/development/libraries/telepathy/glib/default.nix

@@ -15,6 +15,10 @@ stdenv.mkDerivation rec {
 
   buildInputs = [pkgconfig libxslt] ++ stdenv.lib.optional valaSupport vala;
 
+  preConfigure = ''
+    substituteInPlace telepathy-glib/telepathy-glib.pc.in --replace Requires.private Requires
+  '';
+
   meta = {
     homepage = http://telepathy.freedesktop.org;
   };