title: JQuery serializeArray does not include selects without selected options
body: <p>I use the <code>serializeArray()</code> method to get the HTML form as JS object. When the form has a select control with "multiple" options but no option is selected the object is not serialized.</p>
  
  <p>Here is an example: <a href="https://fiddle.jshell.net/tfzxmr9d/1/" rel="nofollow">https://fiddle.jshell.net/tfzxmr9d/1/</a></p>
  
  <p>It works fin when it has one or more values. It should return an object with the control name and empty or null value. Is it working as expected ?</p>