Add support for different light patterns

[tgru]

This is already mentioned in your (@j1nx ) post in the Mycroft Community Forum. It would be nice if the color and pattern is changeable from the default google colors.

I looked into the code of the pixel ring library and there are patterns defined to resemble the echo or google home. Tested it and a simple call of pixel_ring.change_pattern('echo') does the trick plus maybe setting the brightness, because it was a bit dim after changing it back.