title: How to prevent use from putting non valid value in the autocomplete field?
body: <p>How do I prevent a user from inserting a value that is not in the source of the autocomplete?</p>
  
  <pre><code>var items=  [
      { "label": "Account Administration" },
      { "label": "Applications"},
      { "label": "General Information" },
      { "label": "Hardware" },
      { "label": "Network" },
      { "label": "Operating System" },
      { "label": "Remote Connectivity" }
  ];
  $(".autocomp").autocomplete({ source: items});
  </code></pre>