kete: while disconnected, print a message to that effect

$> ./tools/tuhi-kete.py
Tuhi shell control
WARNING: Tuhi daemon not running
tuhi> list
Not connected to the Tuhi daemon

Better than just a noop

tools/tuhi-kete.py

@@ -614,6 +614,7 @@ class TuhiKeteShell(cmd.Cmd):
         # Restore the logger facility to something sane:
         self._log_handler.set_normal_mode()
         if self._manager is None and line not in ['EOF', 'exit']:
+            print('Not connected to the Tuhi daemon')
             return ''
         return line