test-signal.py: Adapt to disconnectAll rename.
test-signal.py: Adapt to disconnectAll rename.

Change-Id: I14bc53c1c98e6d62783e8457f813aaa8025094cb
Reviewed-on: http://gerrit.aldebaran.lan/26703
Reviewed-by: mnottale <e3ccf1b6558404e921a21fa09cebb1153b50ec36@aldebaran-robotics.com>
Tested-by: mnottale <e3ccf1b6558404e921a21fa09cebb1153b50ec36@aldebaran-robotics.com>

aldebaran/libqi,vbarbaresi/libqi,bsautron/libqi,aldebaran/libqi,aldebaran/libqi