Kafka replicator

Kafka replicator bridges messages from upstream topic to downstream topic with configurable re-partitionning strategy.

RUST_LOG=debug cargo run --bin=replicator --verbose -- fixtures/example-config.yml

RUST_LOG=debug cargo run --bin=producer --verbose -- --client=cl_1_client_1 --num=100000 --topic=topic2 fixtures/example-config.yml