Lets clusters define their preferred (prod) replication factor

so that we can omit replication-factor when creating topics,
as we benefit from reusing such commands or definitions across dev-qa-prod.

Author: solsson

kafka/10broker-config.yml

@@ -107,6 +107,9 @@ data:
     # the brokers.
     num.partitions=1
 
+    default.replication.factor=3
+    min.insync.replicas=2
+
     # The number of threads per data directory to be used for log recovery at startup and flushing at shutdown.
     # This value is recommended to be increased for installations with data dirs located in RAID array.
     num.recovery.threads.per.data.dir=1