Implement S3 Select API

[alamb]

This is some musing about implementing the S3 select API

https://docs.aws.amazon.com/AmazonS3/latest/API/API_SelectObjectContent.html

Some possible improvements:

1. Could support much more SQL than listed on https://docs.aws.amazon.com/AmazonS3/latest/userguide/s3-select-sql-reference-select.html
2. Could return parquet content (rather than just CSV / JSON)