Add types and files fields to package.json
Add types and files fields to package.json

https://docs.npmjs.com/cli/v6/configuring-npm/package-json#files
https://www.typescriptlang.org/docs/handbook/declaration-files/publishing.html#including-declarations-in-your-npm-package
https://github.blog/changelog/2020-12-16-npm-displays-packages-with-bundled-typescript-declarations/
tkoenig89/express-static-gzip,tkoenig89/express-static-gzip