v2: Add basic 3DOF Index Controller support
Only the "gen1" watchman usb protocol is supported (almost same as vive wand).
Note: Lighthouse v2 data is not properly ignored, the IMU data is only parsed correctly
when controller is not hit by lighthouse lasers.
Supported:
* trigger value
* trigger button
* trackpad x, y
* trackpad touch
* thumbstick x, y
* thumbstick click
* system click
* a click,
* b click
Not supported:
* trigger touch
* touchpad force
* thumbstick touch
* system touch
* a touch
* b touch
* grip squeeze
* finger tracking
This adds a driver for the Vive family of devices based on Philipp
Zabel's ouvrt.
The driver currently only handles the IMU and main board report streams,
but is able to acquire the JSON configuration and utilize it for IMU
calibration as well as distortion configuration.