Feature: Add support for writing single destination per source record

[simonl2002]

Feature description

This request encompasses several things.

Source Connector

• set the source filename into metadata

Destination Connector

• allowoverriding of filename
• single file per record setting to avoid batching.

[simonl2002]

We will do this however, work on this will wait until after better processors work has been completed.

[hariso]

The better processors' work has been completed, so we can triage this again.