Adding unit testing to the tree

[Patrick Georgi]

Hi everybody,

There's some fine work by Jan on Gerrit on the issue of adding unit testing
infrastructure to our tree and I'd like to see it merged soon.

So far, most feedback was by Google folks so this is a heads up for
everybody (and especially those not at Google) to take a look and offer
your input.

The design doc, build infra and demonstration test cases can be found at
https://review.coreboot.org/39893 and the commits that are based on it.

I aim for inclusion near the end of the week unless there's feedback
showing weaknesses in the plan or implementation.

Thanks,
Patrick