Signal Spy: add some tests about waitUntil cancellation
Signal Spy: add some tests about waitUntil cancellation

... and factorize some timeout constants in tests

Change-Id: I6a696b3448907f2c76e52f8b3341e2bdd9b41334
Reviewed-on: http://gerrit.aldebaran.lan/86499
Reviewed-by: jlamotte <70353e7b0c7d18b7fc75605daf0ccba69fcd3222@aldebaran.com>
Tested-by: vpaleologue <cb19838a79eb484e12a6960acfbf7c16dfdb80d9@aldebaran-robotics.com>

aldebaran/libqi,aldebaran/libqi,aldebaran/libqi