title: json-path: first element from an array fiilter result
body: <p>I'm new to <code>json-path</code>, but I have often used <code>xpath</code>.
  My problem is to extract, with <code>json-path</code>, the <code>nth</code> element of an array resulting  from a previus filter. 
  For example with the following <code>json</code></p>
  
  <pre><code>{
      "store": {
          "book": [
              {
                  "category": "reference",
                  "author": "Nigel Rees",
                  "title": "Sayings of the Century",
                  "price": 8.95
              },
              {
                  "category": "fiction",
                  "author": "Evelyn Waugh",
                  "title": "Sword of Honour",
                  "price": 12.99
              },
              {
                  "category": "fiction",
                  "author": "Herman Melville",
                  "title": "Moby Dick",
                  "isbn": "0-553-21311-3",
                  "price": 8.99
              },
              {
                  "category": "fiction",
                  "author": "J. R. R. Tolkien",
                  "title": "The Lord of the Rings",
                  "isbn": "0-395-19395-8",
                  "price": 22.99
              }
          ],
          "bicycle": {
              "color": "red",
              "price": 19.95
          }
      },
      "expensive": 10
  }
  </code></pre>
  
  <p>I want to  match the first book with category "fiction"</p>
  
  <p>I tried with</p>
  
  <pre><code>$..book[?(@.category=='fiction')][0]
  </code></pre>
  
  <p>but seems it does not work with any of the online evaluation tools.</p>
  
  <p>Where is the error?</p>
  
  <p>Thanks in advance.</p>