Drop the dependency on s3fs

[LinusU]

I think it would be a good improvement to drop the dependency on s3fs and instead use aws-sdk directly. This would save the extra dependencies and give us access to upstream updates quicker.

I would be happy to provide the code if no one beats me to it.

On a related note, it seems like uploading to s3 from multer is very popular. How would you feel about getting some help on maintaining this module? I would personally be happy to hop on as a maintainer. Since it's such a small module I think the most work would be to cut new releases when dependencies (probably only aws-sdk) updates, and to answer questions from users.

I'm linusu on npm 😄

[anacronw]

I'd love help on this module! The only real value I added was making sure the integration worked - the rest was trivial yet I didn't see other modules doing the same thing. I don't have much time myself on open source unfortunately.

I'd be happy to take any pull requests. I can also add you as a maintainer