Documentation of firmware design & execution flow

[jacobeva]

After discussion with @nathmo, he said it is likely a good idea to have a document explaining how the firmware functions. I agree.

A document should be drawn up that explains the overall design and execution flow of the firmware, so as to make it easier to navigate for those who wish to contribute to the project.

That said, this largely still ties in with issue #1, as generally the source code should be the documentation, suckless style. However, I do see how an overview document, and better documentation of the KISS interface in particular, would make RNode much easier to contribute to and utilise.

See #18 (comment)