[POC] Move from CJS to ESM

[PopGoesTheWza]

Fixes no known issues but enable use of ESM dependencies.

• [?] npm run test succeeds.
• npm run lint succeeds.
• Appropriate changes to README are included in PR.

[PopGoesTheWza]

@sqrrrl please review this PR. No fix nor new feature... but it enable the uses of ESM dependencies (i.e. package.json now uses latest version of many packages from sindre horsus)

Trend is popular package switching to ESM. Hence in order to benefit new feature and fix from dependencies, it seem sensible to switch from CJS to ESM.

[sqrrrl]

Thanks. Was just starting to look at updating dependencies and it was quickly becoming a rat hole :)

[PopGoesTheWza]

Thanks. Was just starting to look at updating dependencies and it was quickly becoming a rat hole :)

With this PR, ESM packages can be used "as is". Most CJS packages should not need any changes (one counter example is fs-extra)

[PopGoesTheWza]

This Pure ESM package gist was helpful in order to transition.