title: Filter Array Not in Another Array
body: <p>Need to  filter one array based on another array. Is there a util function in knock out ? else i need to go with javascript</p>
  
  <p>First  :</p>
  
  <pre><code>var obj1 = [{
      "visible": "true",
      "id": 1
  }, {
      "visible": "true",
      "id": 2
  }, {
      "visible": "true",
      "id": 3
  }, {
      "Name": "Test3",
      "id": 4
  }];
  </code></pre>
  
  <p>Second  :</p>
  
  <pre><code>var obj2 = [ 2,3]
  </code></pre>
  
  <p>Now i need to filter obj1 based on obj2 and return items from obj1 that are not in obj2 omittng 2,3 in the above data (Comparison on  object 1 <strong>Id</strong>)</p>
  
  <p>output:</p>
  
  <pre><code>[{
      "visible": "true",
      "id": 1
  }, {
      "Name": "Test3",
      "id": 4
  }];
  </code></pre>