GenericObject: Support cast from template object to ObjectPtr.
GenericObject: Support cast from template object to ObjectPtr.

Change-Id: If911e0aca4827c2d3ec2c25ba712467b64fadaa2
Reviewed-on: http://gerrit.aldebaran.lan:8080/18061
Reviewed-by: cgestes <ddb78fe00abb42f91254c16a0860e38eb0781789@aldebaran-robotics.com>
Reviewed-by: mnottale <e3ccf1b6558404e921a21fa09cebb1153b50ec36@aldebaran-robotics.com>
Tested-by: mnottale <e3ccf1b6558404e921a21fa09cebb1153b50ec36@aldebaran-robotics.com>

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