Updating copyright notices for 2020.

docker/dockerfile-build-centos

@@ -1,3 +1,4 @@
+# Copyright (c) 2019-2020 Advanced Micro Devices, Inc. All rights reserved.
 # This Dockerfile provides a starting point for a ROCm installation of rccl
 
 # Parameters related to building rccl

docker/dockerfile-build-ubuntu-rock

@@ -1,3 +1,4 @@
+# Copyright (c) 2019-2020 Advanced Micro Devices, Inc. All rights reserved.
 # Parameters related to building rccl
 ARG base_image
 

docker/dockerfile-install-centos

@@ -1,3 +1,4 @@
+# Copyright (c) 2019-2020 Advanced Micro Devices, Inc. All rights reserved.
 # Parameters related to building rccl
 ARG base_image
 

docker/dockerfile-install-ubuntu

@@ -1,3 +1,4 @@
+# Copyright (c) 2019-2020 Advanced Micro Devices, Inc. All rights reserved.
 # Parameters related to building rccl
 ARG base_image