Update README to document the `data` and `res` return values.

[markstos]

I also made a second commit to update the History and package.json files so that this change is release-ready if accepted.

Thanks.

[aheckmann]

when opening a PR it is best practice to leave the version bump out. the project owner will release appropriately. in this case, we don't need to release at all b/c its just a readme change.

[markstos]

Thanks for letting me know.

I realize it's not a bug in the code, but as a best practice, return values are documented in published releases.

Considering there's only basically only one public method and none of it's return values are documentation, it seems like an important bit of information. While err and res might be guessed, data is a completely generic term.

Users shouldn't have to dig around in Github to find such a basic piece of information.

[aheckmann]

thanks for the contribution! will merge one the version bump stuff is removed.

[markstos]

Thanks for the reply.

I'm amended the last commit to be only a proposed changelog entry. No version mentions.

You can merge or cherry pick only the README update if you didn't want a proposed Changelog entry, either.

I'm checking out some of your Soundcloud work now.

[aheckmann]

thanks!