title: source only allowed values in JQuery UI autocomplete plugin
body: <p>Is is possible to restrict the user input to only the source values with <a href="http://jqueryui.com/demos/autocomplete" rel="nofollow">JQuery autocomplete plugin</a>?</p>
  
  <p>For example, if the source array contains <code>"Bold","Normal","Default","100","200"</code>, the user is allowed to only type those values.</p>