title: Load only part of Ravendb document array item
body: <p>Let's imagine document with localisations like this:  </p>
  
  <pre><code>{  
      "Id":"product/1",  
      "CategoryId":"categories/1",  
      "Translations":[  
          { "Lang": "en", "Title:"en title"},  
          { "Lang": "hr", "Title:"hr title"}
      ]
  } 
  </code></pre>
  
  <p>and I want to get from Raven projected/flattened/filtered results that looks like this, if I query for index <strong>CategoryId:"categories/1" AND Lang:"en"</strong>:  </p>
  
  <pre><code>{  
      "Id":"product/1",
      "CategoryId":"categories/1",  
      "Lang":"en",  
      "Title":"en title"
  }
  </code></pre>
  
  <p>so basically, document contains localized strings in array, and I want to get only one language. Filtering on client is not a problem, but how to do it on raven server, with Transformer?  </p>
  
  <p>Or, can you suggest some other document structure for storing localised content? Currently, I have separate documents Product and ProductTranslation (for every language), but would like to have it all under one doc (looks more OO:/)</p>