title: Difference between jQuery.isPlainObject() and jQuery.isEmptyObject()
body: <p>Can anyone explain what's the difference between jQuery.isPlainObject() and jQuery.isEmptyObject()? They both return true for an object that has no properties. Examples</p>
  
  <pre><code>jQuery.isEmptyObject({}); // returns true
  jQuery.isPlainObject({}); // returns true
  </code></pre>
  
  <p>Thanks in advance.</p>