feat: Made the packages public

[thomsmoreau]

In order to let third parties use the package of this library, we moved the pkg folder out of the locked internal folder

[celogeek]

That's too open. I would just share the Input, add some hooks to handle progress or json output, and having a public write that will call inner method.

I've got some idea about this. I need a bit of time to work on it.

[celogeek]

I make the epub / epub options public I need to add a progress parameter so we can use anything we want. I close this one as it's a duplicate of the main branch.