Please backport qjackctl 0.3.9-2 (universe) from quantal

Please backport qjackctl 0.3.9-2 (universe) from quantal to precise.

Reason for the backport:
========================
This version of qjackctl (0.3.9-2) includes a new feature which removes a problem caused by LP Bug #956438.
What The new feature does is that on quitting qjackctl, it kills jackdbus, which sometimes hangs when trying to stop it.
This makes life much easier for new users, who will not have to kill the jackdbus process manually.
Some might go to the length of restarting the system just to have jackdbus available again.

Testing:
========
Mark off items in the checklist [X] as you test them, but please leave the checklist so that backporters can quickly evaluate the state of testing.

You can test-build the backport in your PPA with backportpackage:
$ backportpackage -u ppa:<lp username>/<ppa name> -s quantal -d precise qjackctl

* precise:
[x ] Package builds without modification
[x ] qjackctl installs cleanly and runs

Reverse dependencies:
=====================
The following reverse-dependencies need to be tested against the new version of qjackctl. For reverse-build-dependencies (-Indep), please test that the package still builds against the new qjackctl. For reverse-dependencies, please test that the version of the package currently in the release still works with the new qjackctl installed. Reverse- Recommends, Suggests, and Enhances don't need to be tested, and are listed for completeness-sake.

qjackctl
--------
* djplay
  [x ] precise (Reverse-Depends)
* ubuntustudio-recording
  [x ] precise (Reverse-Depends)
* whysynth
  [x ] precise (Reverse-Suggests)
* ubuntustudio-generation
  [x ] precise (Reverse-Depends)
* jack-mixer
  [x ] precise (Reverse-Suggests)
* tuxguitar-jack
  [x ] precise (Reverse-Suggests)
* jack-keyboard
  [x ] precise (Reverse-Suggests)
* jackd2
  [x ] precise (Reverse-Recommends)
* jackd1
  [x ] precise (Reverse-Recommends)
* vmpk
  [x ] precise (Reverse-Recommends)
* rosegarden
  [x ] precise (Reverse-Suggests)
* ghostess
  [x ] precise (Reverse-Recommends)
* rumor
  [x ] precise (Reverse-Suggests)