title: not_indexed field is stored in index
body: <p>I'm trying to optimize my elasticsearch scheme.</p>
  
  <p>I have a field which is a URL - I do not want to be able to query or filter it, just retreive it.</p>
  
  <p>My understanding is that a field that is defined as <code>"index":"no"</code> is not indexed, but is still stored in the index. 
  (see slide 5 in <a href="http://www.slideshare.net/nitin_stephens/lucene-basics" rel="noreferrer">http://www.slideshare.net/nitin_stephens/lucene-basics</a>)
  This should match to Lucene UnIndexed, right?</p>
  
  <p>This confuses me, is there a way to store some fields, without them taking more storage than simply their content, and without encumbering the index for the other fields?</p>
  
  <p>What am I missing?</p>