* Move gRPC error intercetpors to api/utils/grpc/interceptors.
* Use error interceptors in api client and mock server.
* Apply suggestions from CR.
* Unwrap FromGRPC errors in middleware.
* Use gRPC auth service in tests instead of external example service.
* It's gRPC!!!
* Fix unit test.
* Add error interceptor to proxy client.
* Fix merge conflict.
This adds proxy peering support. A configurable setting that allows for agents
to connect to a subset of proxies and be reachable through any proxy in the
cluster. This is achieved by creating grpc connections between each proxy
server. Client connections can then be passed between proxies to the desired
agent.
Gabriel Corado