control audio volume from system tray/notification area

 Volti is a lightweight GTK+ application for controlling audio
 volume from system tray/notification area.
 .
 Features:
  * no PulseAudio, GStreamer, Phonon etc. only ALSA is needed
  * internal mixer application, either choosing any mixer app
    is possible
  * left click opens volume scale (slider)
  * scroll wheel on tray icon changes volume, increment in
    percents is configurable
  * configurable middle click to toggle 'mute' or 'show mixer'
  * nice tooltip with card and volume info
  * support for multimedia keys
  * support desktop notifications on keys events