GenericValue: handle size for tuple
GenericValue: handle size for tuple

Change-Id: I1a84c1d691688bc7c9ed164284c9e6f016364ed1
Reviewed-on: http://gerrit.aldebaran.lan:8080/14615
Reviewed-by: cgestes <ddb78fe00abb42f91254c16a0860e38eb0781789@aldebaran-robotics.com>
Tested-by: cgestes <ddb78fe00abb42f91254c16a0860e38eb0781789@aldebaran-robotics.com>

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