Add gsutil 4.13 to telemetry/third_party

tools/telemetry/third_party/gsutil/third_party/oauth2client/CONTRIBUTING.md

+Contributing
+============
+
+1.  **Please sign one of the contributor license agreements below.**
+1.  Fork the repo, develop and test your code changes, add docs.
+1.  Make sure that your commit messages clearly describe the changes.
+1.  Send a pull request.
+
+Here are some guidelines for hacking on `oauth2client`.
+
+Using a Development Checkout
+----------------------------
+
+You’ll have to create a development environment to hack on
+`oauth2client`, using a Git checkout:
+
+-   While logged into your GitHub account, navigate to the `oauth2client`
+    [repo][1] on GitHub.
+-   Fork and clone the `oauth2client` repository to your GitHub account
+    by clicking the "Fork" button.
+-   Clone your fork of `oauth2client` from your GitHub account to your
+    local computer, substituting your account username and specifying
+    the destination as `hack-on-oauth2client`. For example:
+
+    ```bash
+    $ cd ${HOME}
+    $ git clone git@github.com:USERNAME/oauth2client.git hack-on-oauth2client
+    $ cd hack-on-oauth2client
+    $ # Configure remotes such that you can pull changes from the oauth2client
+    $ # repository into your local repository.
+    $ git remote add upstream https://github.com:google/oauth2client
+    $ # fetch and merge changes from upstream into master
+    $ git fetch upstream
+    $ git merge upstream/master
+    ```
+
+Now your local repo is set up such that you will push changes to your
+GitHub repo, from which you can submit a pull request.
+
+-   Create a virtualenv in which to install `oauth2client`:
+
+    ```bash
+    $ cd ~/hack-on-oauth2client
+    $ virtualenv -ppython2.7 env
+    ```
+
+    Note that very old versions of virtualenv (virtualenv versions
+    below, say, 1.10 or thereabouts) require you to pass a
+    `--no-site-packages` flag to get a completely isolated environment.
+
+    You can choose which Python version you want to use by passing a
+    `-p` flag to `virtualenv`. For example, `virtualenv -ppython2.7`
+    chooses the Python 2.7 interpreter to be installed.
+
+    From here on in within these instructions, the
+    `~/hack-on-oauth2client/env` virtual environment you created above will be
+    referred to as `$VENV`. To use the instructions in the steps that
+    follow literally, use the `export VENV=~/hack-on-oauth2client/env`
+    command.
+
+-   Install `oauth2client` from the checkout into the virtualenv using
+    `setup.py develop`. Running `setup.py develop` **must** be done while
+    the current working directory is the `oauth2client` checkout
+    directory:
+
+    ```bash
+    $ cd ~/hack-on-oauth2client
+    $ $VENV/bin/python setup.py develop
+    ```
+
+Running Tests
+--------------
+
+-   To run all tests for `oauth2client` on a single Python version, run
+    `nosetests` from your development virtualenv (See
+    **Using a Development Checkout** above).
+
+-   To run the full set of `oauth2client` tests on all platforms, install
+    [`tox`][2] into a system Python.  The `tox` console script will be
+    installed into the scripts location for that Python.  While in the
+    `oauth2client` checkout root directory (it contains `tox.ini`),
+    invoke the `tox` console script.  This will read the `tox.ini` file and
+    execute the tests on multiple Python versions and platforms; while it runs,
+    it creates a virtualenv for each version/platform combination.  For
+    example:
+
+    ```bash
+    $ sudo pip install tox
+    $ cd ~/hack-on-oauth2client
+    $ tox
+    ```
+
+Running System Tests
+--------------------
+
+-   To run system tests you can execute:
+
+    ```bash
+    $ tox -e system-tests
+    $ tox -e system-tests3
+    ```
+
+    This alone will not run the tests. You'll need to change some local
+    auth settings and download some service account configuration files
+    from your project to run all the tests.
+
+-   System tests will be run against an actual project and so you'll need to
+    provide some environment variables to facilitate this.
+
+    -   `OAUTH2CLIENT_TEST_JSON_KEY_PATH`: The path to a service account JSON
+        key file; see `tests/data/gcloud/application_default_credentials.json`
+        as an example. Such a file can be downloaded directly from the
+        developer's console by clicking "Generate new JSON key". See private
+        key [docs][3] for more details.
+    -   `OAUTH2CLIENT_TEST_P12_KEY_PATH`: The path to a service account
+        P12/PKCS12 key file. You can download this in the same way as a JSON
+        key, just select "P12 Key" as your "Key type" when downloading.
+    -   `OAUTH2CLIENT_TEST_P12_KEY_EMAIL`: The service account email
+        corresponding to the P12/PKCS12 key file.
+    -   `OAUTH2CLIENT_TEST_USER_KEY_PATH`: The path to a JSON key file for a
+        user. If this is not set, the file created by running
+        `gcloud auth login` will be used. See
+        `tests/data/gcloud/application_default_credentials_authorized_user.json`
+        for an example.
+    -   `OAUTH2CLIENT_TEST_USER_KEY_EMAIL`: The user account email
+        corresponding to the user JSON key file.
+
+-   Examples of these can be found in `scripts/local_test_setup.sample`. We
+    recommend copying this to `scripts/local_test_setup`, editing the values
+    and sourcing them into your environment:
+
+    ```bash
+    $ source scripts/local_test_setup
+    ```
+
+Contributor License Agreements
+------------------------------
+
+Before we can accept your pull requests you'll need to sign a Contributor
+License Agreement (CLA):
+
+-   **If you are an individual writing original source code** and **you own
+    the intellectual property**, then you'll need to sign an
+    [individual CLA][4].
+-   **If you work for a company that wants to allow you to contribute your
+    work**, then you'll need to sign a [corporate CLA][5].
+
+You can sign these electronically (just scroll to the bottom). After that,
+we'll be able to accept your pull requests.
+
+[1]: https://github.com/google/oauth2client
+[2]: https://tox.readthedocs.org/en/latest/
+[3]: https://cloud.google.com/storage/docs/authentication#generating-a-private-key
+[4]: https://developers.google.com/open-source/cla/individual
+[5]: https://developers.google.com/open-source/cla/corporate