Supported NodeJS Versions

[harshkhandeparkar]

Currently IS supports and runs tests on NodeJS v10 and v12. Node 10 has reached EoL and dependencies such as this are no longer compatible.

Also support for the current LTS v14 and upcoming versions needs to be discussed.

[jywarren]

I think let's drop 10 and support 14!

[harshkhandeparkar]

Adding 16 won't hurt either, right?

[harshkhandeparkar]

Checklist:

• update github actions
• update package.json (add engines field and module field)

ref: https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c and https://blog.sindresorhus.com/get-ready-for-esm-aa53530b3f77

Please add anything else I missed out :)