title: Add one month to gmdate using current format
body: <p>Hello I have the following php code:</p>
  
  <pre><code>$date = gmdate("Y-m-d\TH:i:s\Z"); /*Format: '2015-05-24T00:00:00Z'*/
  </code></pre>
  
  <p>How would I simply add 1 month to the above date while keeping the same format?</p>
  
  <p>I tried a few things that lead to nowhere, I am sure there should be a way of doing it that I can't seem to find.</p>
  
  <p>Any help is much appreciated!</p>
  
  <p>Thanks,
  Al</p>