read color does not need to specify led as 3rd arg

and in the response, concerned led is define by 0 or 1, not 1 or 2 as in the request.
Merge pull request #148 from avernois/patch-1

read color does not need to specify led as 3rd arg
you are correct. thanks @avernois!  (and actually the 'ledn' argument is "0,1 = 1st LED, 2 = 2nd LED, 3..18 = 3rd-18th LED (if you install those)"