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For steps 5 and 6, we can add a maven profile that takes a property that is a path for additional artifacts to include.  It can copy those to the right place, then do whatever it is doing today.

Upgrading Hydrator

We are making backwards incompatible changes to the etl config. This will require a Hydrator upgrade, which will have its own upgrade process that is not tied to the cdap upgrade process.

The Hydrator upgrade tool will have a command that converts an old config into a new config. It will also have a command that will take cdap host/port/credential information and convert all 3.2.x pipelines into 3.3.x pipelines. 

New ETL Application features

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