Please sync quodlibet 0.23-1 from Debian Sid (main)

This is on my wishlist too.

Also sync python-mutagen 1.6 from Debian which quodlibet uses to handle audio metadata.

Including relevant information per new sync policy.

New Debian changes:

quodlibet (0.23-1) unstable; urgency=low
 .
   * New upstream release.
     - Version number is correct (closes: #381393).
   * Change dependencies to use python2.4-foo, as we are using a non-default
     python version (closes: #367221).

quodlibet (0.22-2) unstable; urgency=low
 .
   * Fix build-deps: we need to depend on python2.4-dev now, not python-dev.
 .
 quodlibet (0.22-1) unstable; urgency=low
 .
   * New upstream version.
     - Python 2.4 is now required.
     - New optional tray icon plugin; the plugin itself is included in
       quodlibet-plugins from 20060713-1 onwards (closes: #356726).
   * Add watch file.
   * Install upstream changelog as changelog.gz (closes: #375437).
     - Thanks to Bastian Kleineidam <email address hidden> for the patch.
   * Use correct clean target.
   * Add libmpcdec3 dependency to exfalso.
   * Bump python-mutagen dependency up to 1.4.

No previous Ubuntu changes to override.

[Updating] quodlibet (0.21.1-1 [Ubuntu] < 0.23-1 [Debian])
 * Trying to add quodlibet...
  - <quodlibet_0.23.orig.tar.gz: downloading from http://ftp.debian.org/debian/> - <quodlibet_0.23-1.dsc: downloading from http://ftp.debian.org/debian/>
  - <quodlibet_0.23-1.diff.gz: downloading from http://ftp.debian.org/debian/>
I: quodlibet [universe] -> quodlibet_0.21.1-1 [universe].
I: quodlibet [universe] -> quodlibet-ext_0.21.1-1 [universe].
I: quodlibet [universe] -> exfalso_0.21.1-1 [universe].