Small fixes

Summary: Pull Request resolved: https://github.com/fairinternal/fairseq-py/pull/835

Differential Revision: D16904038

Pulled By: myleott

fbshipit-source-id: 2c9d0b913f8d688297ac80fcabd905bd1397f66a

validate.py

 #!/usr/bin/env python3 -u
-# Copyright (c) 2017-present, Facebook, Inc.
-# All rights reserved.
+#!/usr/bin/env python3 -u
+# Copyright (c) Facebook, Inc. and its affiliates.
 #
-# This source code is licensed under the license found in the LICENSE file in
-# the root directory of this source tree. An additional grant of patent rights
-# can be found in the PATENTS file in the same directory.
+# This source code is licensed under the MIT license found in the
+# LICENSE file in the root directory of this source tree.
 
 import torch