Completely removed the 'joined' field from Uploads as it is not needed, removed redis persistence on development docker-compose, made sure that results are not kept for celery tasks.

Added custom serializer to celery test config, downgraded log level for log calls on successfull process finish.

Refactored re-processing to use pipelines, fixed issue with calculation processes not being updated.

Added PipelineContext object and corresponding custom serializer to make working with pipelines easier.