Quick Editor: missing Github and documentation improvements

Maybe the quick editor is missing a link in the package.json but on the NPM page for the Quick Editor package it doesn't show links to Github and documentation.

https://www.npmjs.com/package/@gravatar-com/quick-editor

Compare to:

https://www.npmjs.com/package/@gravatar-com/hovercards

As well as this the contributing and license links on NPM go to a 404.

Inspect the Quick Editor package.json and compare its npm metadata with the hovercards package shown in the issue. Check the Github, documentation, contributing, and license links on the published Quick Editor npm page; done means all four links appear and resolve without 404 errors.

Written by the indexing model from the issue text.