`KafkaConsumerActor` should be public API

[ismaelhamed]

I've noticed the KafkaConsumerActor feature to share a KafkaConsumer instance via the PlainExternalSource is implemented but is kept internal.

[Aaronontheweb]

cc @Arkatufus

[Arkatufus]

@ismaelhamed This is fine, what you need to do is pass a consumer factory delegate function to the ConsumerSettings<TKey, TValue> class instance like so:

var consumerSettings = ConsumerSettings<string, string>.Create(system, null, null)
    .WithBootstrapServers("localhost:29092")
    .WithGroupId("group1")
    .WithProperty("session.timeout.ms", "6000")
    .WithConsumerFactory(settings => myConsumer);

[ismaelhamed]

@Arkatufus are we talking different use cases? See documentation