Publishers should be able to send mutliple topics from the same endpoint.

[RoboDoig]

Currently, a publisher socket defines its endpoint and topic in properties that are set on creation. This means that publishers are unable to stream several topics from the same endpoint as creating a 2nd publisher with the same endpoint and different topic will throw an 'address already in use' exception.

The intended behavior of a Publisher is to be able to stream multiple topics from the same endpoint, so Publishers should instead accept streams of e.g. Tuple<string, byte[]> (topic, payload)

Alternatively, create a transform node with a topic as a property that transforms a data stream to this Tuple or a 'PublisherMessage' class which is accepted by Publishers.