Write up recommendations for publishing packages

[lemonmade]

This will probably involve deciding when to publish something in the Shopify namespace (@shopify/package-name) versus just doing a regular publish, and some recommendations on versioning, building, etc.

IMO we should also remove most (if not all) of the packages from this repo and have them conform to those recommendations. The monorepo thing is interesting but I think a bad fit for the set of packages we have now, and will only become more confusing as we have more npm packages to manage.