Document logger usage

[kulttuuri]

First of all, thank you for the fantastic project! One think that I came across today was that I needed to add information to run.log file when app has been built.

I noticed the log object in Readme file but had to figure out usage for it myself. I think that it would make things easier for anyone just to have small part in documentation related to logger, how to use it and couple examples.

Thanks! :)

[wojtkowiak]

Hey,
that's a good point. I would be more than happy to see a PR with this if you could at least draft it. If you do not have time, I will try to take care of it for 3.0

[kulttuuri]

Thanks! I have changed my primary job and do not have time for this anymore.