Add PicardUSB device adapter

[marktsuchida]

Picard Industries devices using their PiUsbSDK.

For now, just supports USB Gradient Wheel and USB Side Flipper.

• Test side flipper
• Side flipper Busy() - add extra delay?
• Test gradient wheel
• Gradient wheel Busy() - add extra delay?
• SDK must be in 3rdpartypublic
• SDK DLL conflicts with PicardStage adapter; decide what to do (probably just ship new one)

[marktsuchida]

Might need to revisit the choice of making the Side Flipper a Shutter device, because the current shutter is closed on shutdown (unloadAllDevices() or CMMCore destructor). That's usually safe for shutters, but an arm swinging when closing MM may not be great.