Make a Kafka Cluster's meta data accessible

[felixschlegel]

Idea

Create a dedicated MetaData type that enables users to:

• get all partitions for a topic

Note: This is a discovery task that might be extended or abolished in the future.

[mr-swifter]

As well as portions it would be nice to have access to entire metadata information, like:

• available brokers (host / port)
• leadership information
• replicase information
• count in sync replicas