Include replica set initiate

This PR adds a pillar value 'mongodb.configuration.auto_initiate_replica_set_params' which when set to a valid parameter string for the 'mongo_initiate_replica_set' helper will call it during the salt run.

This has the net result of ensuring that other Mongo setup operations later down the stack -- such as creating users and indexes -- can happen automatically.

The reason this is not done normally is that replication generally should be added after data has been restored. Staging and Production environments, for example, would typically need this left as a manual step.


NB: also added the missing shipment of log files to logstash.