Chapter 7 - Eslint, Flow, Jest code is really hard to make working in 2018

[ekonoval]

Hey Stoyan, I'm reading chapter 7 of your React book and it's really hard to make the code working (especially for a novice in all that fancy instruments), some libraries are obsolete, some configs are not working, though I've managed to pull things together but it took a lot of time. So I thought maybe it would be useful for other folks to see real working examples without wasting a lot of time (though it was useful for me) If you don't mind I'll post a link to working examples of chapter 7 (without real tests yet) here https://github.com/ekonoval/reactBook7QA