Now only jid-multi isn't handled.

If the entity has at least one command exposed, it will be displayed as
a radio button. Other changes: run python interpreter without optimalizations,
otherwise asserts doesn't work. Names of widgets in the glade file were
changed a bit.

Added: glade file for commands window, src/adhoc_commands.py with a class
to create/manage the window. For now, progressbar bounces :-).