To support some uses cases, kroxy needs to be able to forward requests from one proxy instance to other in the same pool. An example use-case is partition limit validation, where in order to properly enforce a count in a thread safe fashion, we need to route all 'create topic' requests through a single proxy instances.

The idea is build a generic API that allows a Kafka RPC to be enveloped, fowarded to the another kroxy which will process it and return the response to the originating kroxy.