Use RenovateApp

[bahmutov]

Instead of Greenkeeper.io

• renovate understands package lock files right away
• it can merge changes and is very configureable

Renovate app info: https://glebbahmutov.com/blog/renovate-app/

Gleb

• add renovate app configuration, probably allow merging patches for now
• remove Greenkeeper badge and add renovate badge
• make pull request

Jennifer

• remove this project from greenkeeper app
• install RenovateApp https://renovateapp.com/ and enable it for this repo only