Add "webpack-cli" bot to the repo

[evenstensberg]

Do you want to request a feature or report a bug?

What is the current behavior?
Right now, we do not have any bot that will improve contributors experience, it would be nice to add a bot that looks at tests and adds labels etc on demand.
If the current behavior is a bug, please provide the steps to reproduce.

N/A
What is the expected behavior?
A bot that is added to the repo
If this is a feature request, what is motivation or use case for changing the behavior?
Better Developer Experience
Please mention other relevant information such as the browser version, Node.js version, Operating System and programming language.

A nice starting point is to look at the botfile in the webpack repo and adjust to this one

[ematipico]

What the bot should do? The same thing that the bot inside webpack does?

[evenstensberg]

Yep, just adjust it to our labels, and it should looks for our unit tests instead of Appveyor etc

[ematipico]

I'd like to take the PR if anybody else wants to

[evenstensberg]

Go for it @ematipico !