create e-ink display driver based on remote script

A script in streamingstore can drive the e-ink displays. This way, the displays update when there is a new script.

For this to work, a couple of things should be fixed:

• every time a script is loaded, the screen should be blanked
• fonts should be installed
• Lua interface for images and fonts
• Lua interface for displaying an image (display()?)
• emulator which writes images as png files
• config file with location of script and streamingstore server

Demo display program:

• location of cats
• time/date
• outside temperature + weather + rain (in mm). Use https://openweathermap.org/price
• solar production / power consumption
• news headlines