Add Sidekiq and Kafka. 

Also:
+ KafkaEvent to publish arbitrary info about models, still kind of a work in progress
+ ClassificationLifecycle management moved to a sidekiq worker
+ MultiKafkaProducer Module to abstract between jruby-kafka and poseidon. 

When running jruby you'll also need to use jbundler to manage Kafka libraries. 
Also re delay: 

> I strongly recommend avoiding delaying methods on instances. This stores object state in Redis which can get > out of date, causing stale data problems.

https://github.com/mperham/sidekiq/wiki/Delayed-extensions#activerecord