feature request: `aws s3 cat` command

Hi team. It'd be great to have an `aws s3 cat` command to preview text files via the aws cli. I often have to `COPY` data into Redshift from S3 and having the ability to see the first few rows would be super handy for seeing whether there is a header, what data types I would need in my schema, what delimiter has been used etc.

Thanks!