This is a Logstash component which reads processed logs from Kafka
and writes them to Elasticsearch (or some other backend supported by
Logstash).

Ingesting the logs from this service with Fluentd will be covered under
a different commit.

Change-Id: I2d722991ab2072c54c4715507b19a4c9279f921b
Partially-Implements: blueprint monasca-roles