Keyboard/#59: Add a tray icon for the keyboard

Bug report from rhaamo on 20/05/2012 21:36:23
A tray icon would be very useful to interact with the virtual keyboard easily:
  • show/hide
  • set layout
  • quit...

Note that it only makes sense when the keyboard is not in embedded mode, where the parent application is responsible for managing this (like the Panel applet).

This feature is now implemented.
The tray icon is now implemented, and handles single clicks by toggling visibility. With the popup menu implemented this report will be closed.

This will likely be done without layout selection, which is tracked in a separate report (Keyboard/#51).