- https://docs.npmjs.com/files/package.json
- https://yarnpkg.com/lang/en/docs/package-json/
- http://wiki.commonjs.org/wiki/Packages/1.1
- https://stackoverflow.com/questions/10065564/add-custom-metadata-or-config-to-package-json-is-it-valid
- http://browsenpm.org/package.json
https://stackoverflow.com/questions/32037150/style-field-in-package-json
https://github.com/defunctzombie/package-browser-field-spec