Update device.py

[Slasktra]

To turn off the LED completely Bit 4 in register LEDx_OFF_H should be set to 1

[coveralls]

Coverage decreased (-0.7%) to 96.032% when pulling 8bc7d8f on Slasktra:patch-1 into 7747900 on voidpp:master.

[Slasktra]

I have no ideas what coveralls is doing. What is needed is a change in the original device.py

def value_high(val):
return (val >> 8) & 0xFF

needs to be changed to:

def value_high(val):
if val==0:
return 16 #Turn of LED
else:
return (val >> 8) & 0xFF

This will instruct the PCA9685 to turn off the LED completely.