Add a led constant for black.

This way we can avoid doing ev3.Leds.set_color(ev3.Leds.RIGHT, (0,0))
which is hard to discover.

Author: ensonic

ev3dev/brickpi.py

@@ -53,6 +53,7 @@ class Leds(object):
     LED1 = ( blue_led1, )
     LED2 = ( blue_led2, )
 
+    BLACK = ( 0, )
     BLUE = ( 1, )
 
     @staticmethod

ev3dev/ev3.py

@@ -55,6 +55,7 @@ class Leds(object):
     LEFT = ( red_left, green_left, )
     RIGHT = ( red_right, green_right, )
 
+    BLACK = ( 0, 0, )
     RED = ( 1, 0, )
     GREEN = ( 0, 1, )
     AMBER = ( 1, 1, )