title: Apache NIFi MergeContent processor - set demarcator as new line
body: <p>I want to use MergeContent processor to merge tweets to bulk insert into Elasticsearch index. For this I need command and tweets (each) to be separated by \n. 
  This is how it should look like</p>
  
  <pre><code>{ action: { metadata }}\n
  { request body        }\n
  </code></pre>
  
  <p>Which will be</p>
  
  <pre><code>{ “index”}
  { tweet1 }
  { tweet2 } 
  </code></pre>
  
  <p>When I put \n as separator the processor actually adds \n as a string instead of new line separator. Is it possible to make it actual new line?
  Also is it possible to leave or make footer empty?</p>
  
  <p>Thanks in advance. </p>