Enclosure API for the visualization of Text to Speech

• Added support to the Enclosure API for the visualization of Text to Speech (using "visemes")
• Mycroft's default Mimic text to speech support now sends visemes to the Enclosure. On a Mycroft unit, this produces lip syncing on screen when it speaks

This integrates changes from the last enclosure code release:

• Illumination changes also impact the matrix dispaly
• Added visemes, which will be visible once changes are made to the TTS client
• Removed the weather icons, added a generic mechanism for sending encoded icons across the serial line

It also breaks display of text and sprites, see #358
This will be addressed in an upcoming release.