Clean up repo file structure

[max-zilla]

The python files in /beam and /rabbitmq can be cleaned up.

• beam should be removed or renamed and code integrated/referenced in ingest_worker

• rabbitmq folder contains ingest worker as well as files like models.py that might be difficult to find, this folder could also be renamed to ingest_worker with those specific files, and if possible generalized functions not used by the worker could be moved outside.