Add npm deploy on release

[barlock]

Adds a hook that will deploy this project to npm whenever a github release is made.

@hadasz You deserve to have your name on publish here, I used mine sense you weren't here. You can change it at any point. If the initial release goes out under me, no harm, it can be easily changed.

https://docs.travis-ci.com/user/deployment/npm/#npm-auth-token

☝️ How to add your token.