Add ApplicationClient addOnClientReadyHandler()
This is especially needed for the KafkaApplicationClient, letting a given handler be invoked when the Kafka producer
is ready.
Also introduce a lifecycleStatus in AbstractServiceClient, preventing successive start() invocations.
@calohmn Are you still working on this? Do you want/need this in 2.0.0?
@sophokles73 I'm still on it, yes. But I think this should be merged after the 2.0.0 release.
@calohmn is this ready to be merged?
@sophokles73 Not yet.
I've added the lifecycleStatus handling now directly in ProtonBasedApplicationClient in order to implement the added addOnClientReadyHandler method.
Changing AbstractServiceClient would have meant a lot more changes.