title: MongoDB limit and number of documents returned
body: <p>I have the following Mongo database:</p>
  
  <p>db.group:</p>
  
  <pre><code>{id: 1, name:"a"}  // index == 1
  {id: 2, name:"b"}  // index == 2
  {id: 13, name:"c"} // index == 3
  {id: 14, name:"d"} // index == 4
  {id: 51, name:"e"} // index == 5
  {id: 52, name:"f"} // index == 6
  {id: 61, name:"g"} // index == 7
  {id: 88, name:"h"} // index == 8
  </code></pre>
  
  <p>I am implementing pagination and I'd like to return 3 documents, starting from the index 4 (1-based, not zero based), which would be </p>
  
  <pre><code>{id: 14, name:"d"} // index == 4
  {id: 51, name:"e"} // index == 5
  {id: 52, name:"f"} // index == 6
  </code></pre>
  
  <p>I know I can use <code>.limit</code> to limit the number of records returned, but how do I say the <code>limit</code> should start from the index 4?</p>