Customizable Cable Lockdown V2

The http://enablingthefuture.org e-NABLE R&D group is looking for a means of locking down a control line when a finger is in position, so the position can be held without holding the control line, and thus the wrist or elbow, in position. For example, lock fingers around a bike handle, then bike without having to maintain tension on the wrist.

This is a 'work in progress' exploring an approach.

V2 Update:
- Added groove in base to increase grip on line when locked down
- Shortened brac