RGB Pulse Width modulator

Simple module to control the colour of a RGB LED with 256 bit resolution.

Port Name	Description
clk	Clock
rst	Reset
an	When set, clear LED pin to illuminate. When cleared, set LED pin to illuminate
half	Indicates second half of illumination cycle
sync	Indicates the beginning of new illumination cycle
rcolor_i	Red value [0...256]
gcolor_i	Green value [0...256]
bcolor_i	Blue value [0...256]
r_o	Red LED pin
g_o	Green LED pin
b_o	Blue LED pin