Fixed silliness with access token verification

src/OAuth2/Exception/InvalidAccessTokenException.php

@@ -0,0 +1,8 @@
+<?php
+
+namespace OAuth2\Exception;
+
+class InvalidAccessTokenException extends OAuth2Exception
+{
+
+}

src/OAuth2/Exception/MissingAccessTokenException.php

@@ -1,8 +0,0 @@
-<?php
-
-namespace OAuth2\Exception;
-
-class MissingAccessTokenException extends OAuth2Exception
-{
-
-}

src/OAuth2/ResourceServer.php

@@ -115,7 +115,7 @@ class ResourceServer
         $result = $this->storages['session']->validateAccessToken($access_token);
 
         if ( ! $result) {
-            return false;
+            throw new Exception\InvalidAccessTokenException('Access token is not valid');
         }
 
         $this->accessToken = $access_token;