Issue #2868 - Adding SPNEGO authentication support for Jetty Client.

Added missing copyright header.

Signed-off-by: Simone Bordet <simone.bordet@gmail.com>

jetty-security/src/main/java/org/eclipse/jetty/security/authentication/AuthorizationService.java

@@ -1,3 +1,21 @@
+//
+//  ========================================================================
+//  Copyright (c) 1995-2018 Mort Bay Consulting Pty. Ltd.
+//  ------------------------------------------------------------------------
+//  All rights reserved. This program and the accompanying materials
+//  are made available under the terms of the Eclipse Public License v1.0
+//  and Apache License v2.0 which accompanies this distribution.
+//
+//      The Eclipse Public License is available at
+//      http://www.eclipse.org/legal/epl-v10.html
+//
+//      The Apache License v2.0 is available at
+//      http://www.opensource.org/licenses/apache2.0.php
+//
+//  You may elect to redistribute this code under either of these licenses.
+//  ========================================================================
+//
+
 package org.eclipse.jetty.security.authentication;
 
 import javax.servlet.http.HttpServletRequest;