anchor.diff:  Logstash elasticsearch output can be configured to use metadata and event type
   for indexing.
   
  -Example Logstash 1.5 config:
  +This logstash configuration file for logstash 1.5 will use the index and
  +document type reported by beats for indexing events right into elasticsearch.
   [source,logstash]
   ------------------------------------------------------------------------------
  -...
  +
  +input {
  +  beats {
  +    port => 5044
  +  }
  +}
   
   output {
     elasticsearch {
  
positive.code:     enabled: true
  
      hosts:
        - logstash1:12345
        - logstash2:12345
        - logstash3:12345
  
      # configure index prefix name
      index: mybeat
  
negative.code:     index => "%{[@metadata][index]}"
      document_type => "%{[@metadata][type]}"
    }
  }
  ------------------------------------------------------------------------------
  
  See the same configuration for logstash 2 releases:
  [source,logstash]
  ------------------------------------------------------------------------------
  
  input {
    beats {
      port => 5044
    }
  }
  
  output {
    elasticsearch {
  