title: How to retrieve timezone offset from GMT+0 in php?
body: <p>I am no expert in php. I know timezones are <a href="http://php.net/manual/en/timezones.php">supported</a> in PHP.</p>
  
  <p>For a given timezone TZ supported by PHP, I need to retrieve the offset (i.e., number of hours and minutes to add or substract) to a known UTC (i.e. GMT+0) to get that time in the TZ zone.</p>
  
  <p>How can I achieve this? Ultimately, I need to get those offsets for all supported timezones in PHP. Thanks. </p>