* BUG: Fix Object.Raise() method.

[DEVELOPMENT ENVIRONMENT]
* BUG: Replace a possible error while filling the toolbox by a warning 
  message.

[GB.DBUS]
* NEW: DBusValues is a new class that must be used when a DBus method canonical
  return several values. It works like DBusVariant.
* NEW: DBus.SplitSignature is new method that allows to split a DBus signature.
* NEW: DBusNull class is renamed as _DBusNull.
  
[GB.DBUS.TRAYICON]
* NEW: TrayIcon popup menu is now exported through the DBusMenu protocol,
  so that it becomes usable on Unity. Consequently, the Menu event will be
  removed.

[GB.DESKTOP]
* NEW: Remove the Desktop.Type property.
* NEW: Add support for Unity.

[GB.GTK]
* NEW: Desktop.Type is now implemented in the GUI components.

[GB.GTK3]
* NEW: Desktop.Type is now implemented in the GUI components.

[GB.QT]
* NEW: Desktop.Type is now implemented in the GUI components.

[GB.QT5]
* NEW: Desktop.Type is now implemented in the GUI components.


git-svn-id: svn://localhost/gambas/trunk@7164 867c0c6c-44f3-4631-809d-bfa615b0a4ec