Cross Fetch Versions Save

⚡️ updated node-fetch to 2.6.1

⚡️ whatwg-fetch is not a prod dependency anymore (#63) ⚡️ updated all dev dependencies.

⚡️ upgraded node-fetch to 2.6.0.

🐞 fixed bug that crashed Safari 9 (#49). ⚡️ added VaporJS code to the project.

🐞 bugfix #35: fixed TypeScript failing on types when dom lib is not present.

🐞 bugfix #38: fixed the browser ponyfill stomping the global fetch function on React Native (thanks @msluther)

• major upgrade of whatwg-fetch to 3.0.0 (see breaking changes)
• minor upgrade of node-fetch to 2.3.0 (see changelog)
• comprehensive test coverage (from 16 specs to 72)
• dropped yarn in favor of npm for package management
• dropped npm in favor of make for tasks runner
• Now you can do import {fetch} from 'cross-fetch' on a browser bundle.
• For ponyfills, fetch.polyfill is now set to undefined instead of false.

🐞 bugfix #26: fixed TypeScript usage without esModuleInterop. (thanks @mattmccutchen)

🐞 bugfix #19: fixed typescript definitions (thanks @evert)

🐞 bugfix: fixed 'realFetch.call is not a function' when cross-fetch is bundled with webpack set to target node (@jamespedid, @alexvetter in #15)