Render real files in doc site

[TinaNikou]

If the doc site could render real files, and line ranges from within real files, then people would be able to click through and actually execute the code themselves, and this would ensure that the code is in a working condition.

Using the recent Build API documentation as an example, this would help to sniff out expected errors which could trip up a learner, such as the type error from passing the invoked board output values to resolve, and it would allow them to have easy access to the full code for both boards to play around with and develop a better understanding of the tools.