Please add per-file licenses

[petrcermak]

The Chromium project (www.chromium.org) pulls in apitools indirectly through the catapult (https://github.com/catapult-project/catapult/) and gsutil (https://github.com/GoogleCloudPlatform/gsutil) source repositories. In order for Chromium to be pulled into various Linux source distributions there's a requirement that all of the third party files pass the Linux licensecheck utility. Currently there are many files in the apitools repository missing per-file licenses. From a current run of licensecheck, they are:

$ licensecheck -r . | grep "No copyright"
./run_pylint.py: *No copyright* UNKNOWN
./samples/storage_sample/storage/__init__.py: *No copyright* UNKNOWN
./samples/storage_sample/storage/storage_v1_client.py: *No copyright* UNKNOWN
./samples/storage_sample/storage/storage_v1.py: *No copyright* UNKNOWN
./samples/storage_sample/storage/storage_v1_messages.py: *No copyright* UNKNOWN
./samples/storage_sample/downloads_test.py: *No copyright* UNKNOWN
./samples/storage_sample/uploads_test.py: *No copyright* UNKNOWN
./ez_setup.py: *No copyright* UNKNOWN
./apitools/__init__.py: *No copyright* UNKNOWN
./apitools/gen/service_registry.py: *No copyright* UNKNOWN
./apitools/gen/util.py: *No copyright* UNKNOWN
./apitools/gen/__init__.py: *No copyright* UNKNOWN
./apitools/gen/extended_descriptor.py: *No copyright* UNKNOWN
./apitools/gen/util_test.py: *No copyright* UNKNOWN
./apitools/gen/command_registry.py: *No copyright* UNKNOWN
./apitools/gen/client_generation_test.py: *No copyright* UNKNOWN
./apitools/gen/message_registry.py: *No copyright* UNKNOWN
./apitools/gen/gen_client.py: *No copyright* UNKNOWN
./apitools/gen/gen_client_lib.py: *No copyright* UNKNOWN
./apitools/base/py/exceptions.py: *No copyright* UNKNOWN
./apitools/base/py/util.py: *No copyright* UNKNOWN
./apitools/base/py/testing/mock.py: *No copyright* UNKNOWN
./apitools/base/py/testing/__init__.py: *No copyright* UNKNOWN
./apitools/base/py/testing/testclient/fusiontables_v1_messages.py: *No copyright* GENERATED FILE
./apitools/base/py/testing/testclient/__init__.py: *No copyright* UNKNOWN
./apitools/base/py/testing/testclient/fusiontables_v1_client.py: *No copyright* UNKNOWN
./apitools/base/py/testing/mock_test.py: *No copyright* UNKNOWN
./apitools/base/py/credentials_lib.py: *No copyright* GENERATED FILE
./apitools/base/py/base_cli.py: *No copyright* GENERATED FILE
./apitools/base/py/stream_slice_test.py: *No copyright* UNKNOWN
./apitools/base/py/encoding_test.py: *No copyright* UNKNOWN
./apitools/base/py/cli.py: *No copyright* UNKNOWN
./apitools/base/py/stream_slice.py: *No copyright* UNKNOWN
./apitools/base/py/http_wrapper.py: *No copyright* UNKNOWN
./apitools/base/py/extra_types_test.py: *No copyright* UNKNOWN
./apitools/base/py/base_api_test.py: *No copyright* UNKNOWN
./apitools/base/py/transfer_test.py: *No copyright* UNKNOWN
./apitools/base/py/batch_test.py: *No copyright* UNKNOWN
./apitools/base/py/__init__.py: *No copyright* UNKNOWN
./apitools/base/py/http_wrapper_test.py: *No copyright* UNKNOWN
./apitools/base/py/list_pager_test.py: *No copyright* UNKNOWN
./apitools/base/py/encoding.py: *No copyright* UNKNOWN
./apitools/base/py/list_pager.py: *No copyright* UNKNOWN
./apitools/base/py/credentials_lib_test.py: *No copyright* UNKNOWN
./apitools/base/py/buffered_stream.py: *No copyright* UNKNOWN
./apitools/base/py/base_api.py: *No copyright* UNKNOWN
./apitools/base/py/util_test.py: *No copyright* UNKNOWN
./apitools/base/py/extra_types.py: *No copyright* UNKNOWN
./apitools/base/py/buffered_stream_test.py: *No copyright* UNKNOWN
./apitools/base/py/batch.py: *No copyright* UNKNOWN
./apitools/base/py/transfer.py: *No copyright* UNKNOWN
./apitools/base/py/app2.py: *No copyright* UNKNOWN
./apitools/base/__init__.py: *No copyright* UNKNOWN

We'd like to ask that per-file licenses be added to these files to make it easier to integrate apitools not only into Chromium, but also Linux distributions in general. Thanks.