periodictask: fix trigger() test

Change-Id: Id94cf298c9ec7cd79a222c5c2b9b799e71ae1ab4
Reviewed-on: http://gerrit.aldebaran.lan/51546
Reviewed-by: pdaouadi <pdaouadi@aldebaran-robotics.com>
Tested-by: pdaouadi <pdaouadi@aldebaran-robotics.com>
Future: fix registration

Change-Id: Ifb6d8dc05d2f595541505705f98a89b34d991950
Reviewed-on: http://gerrit.aldebaran.lan/51509
Reviewed-by: pdaouadi <pdaouadi@aldebaran-robotics.com>
Tested-by: pdaouadi <pdaouadi@aldebaran-robotics.com>
PeriodicTask: use qi clocks

Change-Id: I9fd92f24f98c320522090c445fb85758be45ac50
Reviewed-on: http://gerrit.aldebaran.lan/51555
Reviewed-by: jlamotte <jlamotte@aldebaran.com>
Reviewed-by: pdaouadi <pdaouadi@aldebaran-robotics.com>
Tested-by: pdaouadi <pdaouadi@aldebaran-robotics.com>