Rulle IO

Sorry, I got involved in other things and forgot about it. :) I will create a proper PR in coming days. Technically, I wanted to add a e2e test to...

Just a mocked S3 service, please.

@labianchin

Updated the description.

Thanks for pointing to this (unknown for me) [SQL concept](https://www.postgresql.org/docs/current/sql-comment.html). dbeam currently gets all metadata information about an SQL table using [interface ResultSetMetaData](https://docs.oracle.com/en/java/javase/17/docs/api/java.sql/java/sql/ResultSetMetaData.html). Using anything else (e.g. external utility `psql`)...

The issue with having a mssql jdbc library not included into dbeam package can be solved by providing a option to add(load) a 3rd-party library at runtime.