Contour ShuttlePRO v2 acquired

[rdoursenaud]

I just received a used Contour ShuttlePRO v2 and will start adding support soonish!

The device behaves exactly the same with the 5 buttons of the Express mapping to the 5 buttons above the wheel on the PRO v2. Wheel and jog are identical.

I need to:

• add connection to the new USB PID
• add support for the 10 supplementary buttons
• add the PRO v2 graphic and map the GUI
• find a way to support handling both plugged at the same time

[rdoursenaud]

Initial tests are promising and preliminary support is ongoing in the multidev branch.