title: Java 8 Convert given time and time zone to UTC time
body: <p>I have a time with string type like: <code>"2015-01-05 17:00"</code> and <code>ZoneId</code> is <code>"Australia/Sydney"</code>.</p>
  
  <p>How can I convert this time information to the corresponding to UTC time using Java 8 datetime API?</p>
  
  <p>Also need to considering DST stuff.</p>