blink1: Sample HID app to control a blink(1) mk2 device.

This app demos the new chrome.hid API by controlling a blink(1) mk2 RGB
LED light. More interesting features (don't love RGB sliders?) coming soon!

http://blink1mk2.thingm.com/
Ah, yes, once I have a proper loop over the devices this will go away but for now I'm assuming that if devices is defined it is at least one element long. I'll fix that.