Update generator copyright year.

Some Travis builds appear to fail because generated objects get
2019 copyrights now, and the diff complains.
Reviewed-by: NBernd Edlinger <bernd.edlinger@hotmail.de>
Reviewed-by: NMatt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/7969)

crypto/asn1/charmap.pl

 #! /usr/bin/env perl
-# Copyright 2000-2018 The OpenSSL Project Authors. All Rights Reserved.
+# Copyright 2000-2019 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

crypto/bn/bn_prime.pl

 #! /usr/bin/env perl
-# Copyright 1998-2018 The OpenSSL Project Authors. All Rights Reserved.
+# Copyright 1998-2019 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

crypto/conf/keysets.pl

 #! /usr/bin/env perl
-# Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved.
+# Copyright 1995-2019 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

crypto/objects/obj_dat.pl

 #! /usr/bin/env perl
-# Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved.
+# Copyright 1995-2019 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

crypto/objects/objects.pl

 #! /usr/bin/env perl
-# Copyright 2000-2018 The OpenSSL Project Authors. All Rights Reserved.
+# Copyright 2000-2019 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

crypto/objects/objxref.pl

 #! /usr/bin/env perl
-# Copyright 1998-2018 The OpenSSL Project Authors. All Rights Reserved.
+# Copyright 1998-2019 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