title: Carbon returning the wrong date bug
body: <p>I am manipulating my dates using the php <a href="http://carbon.nesbot.com/" rel="nofollow noreferrer">Carbon</a> package within my Laravel app. I am having some weird results when trying to generate a date (x days in the future)</p>
  
  <p>Please take a look at this code:</p>
  
  <pre><code>$start_date = Carbon::tomorrow('Europe/London');
  $end_date = $start_date-&gt;addDays($tier-&gt;duration_days);
  Log::debug('Carbon::now(): '.Carbon::now());
  Log::debug('Carbon::tomorrow(Europe/London): '.Carbon::tomorrow('Europe/London'));
  Log::debug('$start_date: '.$start_date);
  Log::debug('$end_date: '.$end_date);
  </code></pre>
  
  <p>The code above will print out the following debug lines:</p>
  
  <blockquote>
    <p>2017-04-17 21:46:31] local.DEBUG: Carbon::now(): 2017-04-17 21:46:31<br>
    [2017-04-17 21:46:31] local.DEBUG: Carbon::tomorrow(Europe/London):
    2017-04-18 00:00:00   [2017-04-17 21:46:31] local.DEBUG: $start_date:
    2017-05-16 00:00:00   [2017-04-17 21:46:31] local.DEBUG: $end_date:
    2017-05-16 00:00:00</p>
  </blockquote>
  
  <p>Using Carbon::tomorrow() will print out the correct dates, however using $start_time which technically uses the same function returns the wrong date.
  Can someone advise what could be going wrong here?</p>
  
  <p>FYI I have set Europe/London as my timezone in my <code>config/app.php</code> file.</p>