I have added a pre-configured version of the ws2812b i2s library to the
Arduino code. This removes the need to download and install the ws2812b
i2s library manually. The ws2812b code has been preconfigured to reduce
the temporal compared to the default value. The default value was found
to cause excessive flickering. The readme has been updated to reflect
this change. Also added a note about the maximum number of LEDs (255)
