fix #31 - add backward compatibility support

Author: robocoder

lib/WebDriver/WebDriver.php

@@ -75,6 +75,11 @@ public function session($requiredCapabilities = Browser::FIREFOX, $desiredCapabi
             array(CURLOPT_FOLLOWLOCATION => true)
         );
 
+        // for backwards-compatibility (Selenium 2.33 and below)
+        if (isset($results['info']['url'])) {
+            return new Session($results['info']['url']);
+        }
+
         return new Session($this->url . '/session/' . $results['value']['webdriver.remote.sessionid']);
     }