Log Message:
Update daapd to 0.2.3d

- Fixed a stupid bug in the howl callback. If you had problems with
  daapd showing up in iTunes (i.e. with the mDNS Responder), try this
  update.
- The howl API has changed as of howl 0.9.6.
- Added support for Xing/LAME headers. This speeds up parsing of MP3 files
  and in effect the complete initial scan of the filesystem.
- Fixed a few memory leaks.
- Fixed an issue in the makefile.
- Added auto-updates.
- Clients waiting for updates are automatically notified of changes in the
  database.
- daapd scans the filesystem periodically now. This happens in a
  separate thread.
- Transmissions are compressed with gzip now. This can be turned off with -z