Add controller for Ada hand

[SpaceVR-O1]

[aornelas]

Need to expose the following new functions:

• MoveHome: which interrupts current movement and starts moving towards home position (same as joystick HOME button
• OpenHand
• CloseHand

For all of these, we'll need to figure out a way to make the functions operate like the joystick, where they are progressively activated while pressing the button and stop moving when released (real-time). Perhaps it could work like this:

• assign each point in the trajectory towards the ultimate target (home, open, or closed), a number from 0.0 (current position) to 1.0 (target).
• the functions take that point as a parameter and move towards it

That way, from Unity we can keep calling by incrementing the point while the button is being pressed and the point is less than 1.0.

[aornelas]

We'll also need a GetDeviceID or similar to connect to both arms.

[aornelas]

... or another param to the functions that specify which arm to send command to.

[aornelas]

To activate the scooper trigger and enable cherry picking, we need the following three functions:

• point: retract all fingers except pointer
• pinch: extend all fingers except thumb and middle finger, whose tips should meet
• open: extend all fingers