Add Google authentication

vendor/OAuth/OAuth2/Service/Exception/MissingRefreshTokenException.php

@@ -0,0 +1,17 @@
+<?php
+
+/**
+ * @author David Desberg <david@daviddesberg.com>
+ * Released under the MIT license.
+ */
+
+namespace OAuth\OAuth2\Service\Exception;
+
+use OAuth\Common\Exception\Exception;
+
+/**
+ * Exception thrown when service is requested to refresh the access token but no refresh token can be found.
+ */
+class MissingRefreshTokenException extends Exception
+{
+}