FancyStdoutStream with a docstring

I had a branch for this in my fork, but I'm pretty sure I screwed that up (new to git). I took the relevant commits and added them to the master branch instead to make it "fast forwardable"(?) if that is the right term.

Also, there was a request to add this to the docs, but I couldn't find documentation on the streams and how to configure them outside the references in the configuration.rst. I've added the FancyStdoutStream there and added a docstring with instructions on how to configure it. I'm happy to update the docs however makes the most sense.

Thanks for the patience with my unfamiliarity with git.