title: KnockoutJS Mapping toJS ignore nested keys
body: <p>Can I not ignore nested properties when using toJS in KnockoutJS' mapping plugin?</p>
  
  <p>Example:</p>
  
  <pre><code>var obj = {
      "akey": {
          "anestedkey": "ignore",
          "anotherkey": "value"
      }
  };
  
  console.log(ko.mapping.toJS(obj, {
      "ignore": ["akey.anestedkey"],
  }));
  </code></pre>
  
  <p>Expected output is </p>
  
  <pre><code>{
      akey: {
          anotherkey: "value"   
      }
  }
  </code></pre>
  
  <p>Actual output is</p>
  
  <pre><code>{
      akey: {
          anestedkey: "ignore"
          anotherkey: "value"   
      }
  }
  </code></pre>
  
  <p><strong>JSFiddle: <a href="http://jsfiddle.net/48KVU/" rel="nofollow">http://jsfiddle.net/48KVU/</a></strong></p>