Three-fingered hand 1/9/16

This is an update on the articulating hand. The 3D printer bed could not accommodate the wider five finger hand, while printing the fingers so that they articulated properly. This update adds more specialized channels to the "tendons" that can be used to articulate the fingers. It uses the design of the "index finger squared tip" with slight modifications to prevent the finger from bending back upon itself. If elastic bands are installed on the hooks, and a cord is threaded through the loops, th