update to new attachment version and modernize boilerplate

Author: wescpy

CONTRIBUTING.md

@@ -1,36 +1,28 @@
-# How to become a contributor and submit your own code
-
-## Contributor License Agreements
-
-We'd love to accept your sample apps and patches! Before we can take them, we
-have to jump a couple of legal hurdles.
-
-Please fill out either the individual or corporate Contributor License Agreement
-(CLA).
-
-  * If you are an individual writing original source code and you're sure you
-    own the intellectual property, then you'll need to sign an [individual CLA]
-    (https://developers.google.com/open-source/cla/individual).
-  * If you work for a company that wants to allow you to contribute your work,
-    then you'll need to sign a [corporate CLA]
-    (https://developers.google.com/open-source/cla/corporate).
-
-Follow either of the two links above to access the appropriate CLA and
-instructions for how to sign and return it. Once we receive it, we'll be able to
-accept your pull requests.
-
-## Contributing A Patch
-
-1. Submit an issue describing your proposed change to the repo in question.
-1. The repo owner will respond to your issue promptly.
-1. If your proposed change is accepted, and you haven't already done so, sign a
-   Contributor License Agreement (see details above).
-1. Fork the desired repo, develop and test your code changes.
-1. Ensure that your code adheres to the existing style in the sample to which
-   you are contributing. Refer to the
-   [Google Cloud Platform Samples Style Guide]
-   (https://github.com/GoogleCloudPlatform/Template/wiki/style.html) for the
-   recommended coding standards for this organization.
-1. Ensure that your code has an appropriate set of unit tests which all pass.
-1. Submit a pull request.
+# How to Contribute
 
+We'd love to accept your patches and contributions to this project. There are
+just a few small guidelines you need to follow.
+
+## Contributor License Agreement
+
+Contributions to this project must be accompanied by a Contributor License
+Agreement. You (or your employer) retain the copyright to your contribution;
+this simply gives us permission to use and redistribute your contributions as
+part of the project. Head over to <https://cla.developers.google.com/> to see
+your current agreements on file or to sign a new one.
+
+You generally only need to submit a CLA once, so if you've already submitted one
+(even if it was for a different project), you probably don't need to do it
+again.
+
+## Code reviews
+
+All submissions, including submissions by project members, require review. We
+use GitHub pull requests for this purpose. Consult
+[GitHub Help](https://help.github.com/articles/about-pull-requests/) for more
+information on using pull requests.
+
+## Community Guidelines
+
+This project follows [Google's Open Source Community
+Guidelines](https://opensource.google/conduct/).