CirnOS: new Lua-based OS

CirnOS is an operating system for the Raspberry Pi built for the purpose of usability and simplicity. It provides a simple environment for running Lua scripts on Raspberry Pi. It has no kernel or time management - it is single threaded. You run your code on the device, and that is it.CirnOS has only been tested on the Raspberry Pi Zero, but should work on the original Raspberry Pi and the Zero W.