Export to npm with a normal build and an ES6 build

[atimmer]

What did you expect to happen?

I expect to be able to consume an ES6 project if my toolchain supports it, but I don't want to run babel on all of YoastSEO.js.

What happened instead?

I have to run babel on all of YoastSEO.js or I can't use ES6 modules.

Technical details

For an example of how this could work you could look at Gutenberg. They build to a build folder and a build-module folder. build is then specified as the main entry point in the package.json. build-module is specified as module entry point in the package.json. In both builds all other ES6 syntax is transpired down to ES5.

[omarreiss]

Will come up again during audit.