jack: change package and attr names to 'jack1' and 'jack2'

Currently, we have a 'jack' package with attrname 'jack1d' and a
'jackdbus' package with attrname 'jackaudio'. Make it consistent 'jack1'
and 'jack2' in both package name and attrname.

This aligns the naming with what can be found on the JACK homepage.

Q: what's the difference between jack1 and jack2?
A: http://trac.jackaudio.org/wiki/Q_differenc_jack1_jack2

pkgs/development/libraries/aubio/default.nix

@@ -1,4 +1,4 @@
-{ stdenv, fetchurl, alsaLib, fftw, jackaudio, libsamplerate
+{ stdenv, fetchurl, alsaLib, fftw, jack2, libsamplerate
 , libsndfile, pkgconfig, python
 }:
 
@@ -11,7 +11,7 @@ stdenv.mkDerivation rec {
   };
 
   buildInputs = [
-    alsaLib fftw jackaudio libsamplerate libsndfile pkgconfig python
+    alsaLib fftw jack2 libsamplerate libsndfile pkgconfig python
   ];
 
   configurePhase = "python waf configure --prefix=$out";