title: file_exists() returns false even if file exist (remote URL)
body: <p>My <code>file_exists()</code> returns false even if provided image to check <code>https://www.google.pl/logos/2012/haring-12-hp.png</code> exist. Why?</p>
  
  <p>Below I am presenting full failing PHP code ready to fire on localhost:</p>
  
  <pre><code>$filename = 'https://www.google.pl/logos/2012/haring-12-hp.png';
  echo "&lt;img src=" . $filename . " /&gt;";
  if (file_exists($filename)) {
      echo "The file $filename exists";
  } else {
      echo "The file $filename does not exist";
  }
  </code></pre>