Fix Authenticator interface use statement (#222)

enekochan · dbu · commit 939b53daba74 · 2018-01-18T09:35:16.000+01:00
diff --git a/message/authentication.rst b/message/authentication.rst
@@ -154,7 +154,7 @@ Implement Your Own
 
 Implementing an authentication method is easy: only one method needs to be implemented::
 
-    use Http\Message\Authentication\Authentication;
+    use Http\Message\Authentication;
     use Psr\Http\Message\RequestInterface;
 
     class MyAuth implements Authentication
