Yup: Publish ESM modules

[alexlafroscia]

I'd love to consume this package as an ESM module, so that I can only import the validator functions that I need.

I see that a Rollup configuration is present, but it doesn't seem to actually be used -- the dist folder with the CJS and ESM builds is not published. The only thing published is a lib directory that the Babel CLI produces.

Is there a reason for this? If not, I would be happy to update the build scripts, etc. to publish the dist directory that Rollup produces instead.

[jquense]

I just haven't finished the work to do it yet. Happy to take a contribution adding it

[stramel]

Related to #221

[ReasonX7]

Any updates on it?

[jquense]

nope

[lundn]

Is this going to happen?

[jquense]

maybe!