Update copyright year

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5689)
diff --git a/ssl/ssl_cert_table.h b/ssl/ssl_cert_table.h
index 1376441..0c47241 100644
--- a/ssl/ssl_cert_table.h
+++ b/ssl/ssl_cert_table.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 2017-2018 The OpenSSL Project Authors. All Rights Reserved.
  *
  * Licensed under the OpenSSL license (the "License").  You may not use
  * this file except in compliance with the License.  You can obtain a copy