pisa iit soft hand articulated included

Enrico, this is to include the pisa iit soft hand in walkman.
 
I have a different coman coupler than the one you have. So,  I don't know exactly the transformation you need to place the hand properly or whether it requires an additional part in between.

For bigman I can do the same after the coman is ready in order to avoid redoing fixing.

Gazebo simulation is not ready yet, collisions are not enabled for now, however, you can load and control the hand with a single joint with commands between [0 (open), 1 (close)].

(I already added the pisa-iit-soft-hand project in walkman in the DRC_ninth_sprint_week branch)