oauth2: add CONTRIBUTING

Change-Id: I8775dc83b8fda3954032921f120eab223d1551b4
Reviewed-on: https://go-review.googlesource.com/1651
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

CONTRIBUTING.md

@@ -0,0 +1,25 @@
+# Contributing
+
+We don't use GitHub pull requests but use Gerrit for code reviews,
+similar to the Go project.
+
+1. Sign one of the contributor license agreements below.
+2. go get golang.org/x/review/git-review to install the code reviewing tool.
+3. Get the package by running go get -d golang.org/x/oauth2.
+Make changes and create a change by running git review change <name>, provide a command message, and use git review mail to create a Gerrit CL.
+Keep amending to the change and mail as your recieve feedback.
+
+For more information about the workflow, see Go's [Contribution Guidelines](https://golang.org/doc/contribute.html).
+
+Before we can accept any pull requests
+we have to jump through a couple of legal hurdles,
+primarily a 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](http://code.google.com/legal/individual-cla-v1.0.html).
+- **If you work for a company that wants to allow you to contribute your work**,
+  then you'll need to sign a [corporate CLA](http://code.google.com/legal/corporate-cla-v1.0.html).
+
+You can sign these electronically (just scroll to the bottom).
+After that, we'll be able to accept your pull requests.

README.md

@@ -15,19 +15,4 @@ See godoc for further documentation and examples.
 * [godoc.org/golang.org/x/oauth2](http://godoc.org/golang.org/x/oauth2)
 * [godoc.org/golang.org/x/oauth2/google](http://godoc.org/golang.org/x/oauth2/google)
 
-## Contributing
 
-Fork the repo, make changes, run the tests and open a pull request.
-
-Before we can accept any pull requests
-we have to jump through a couple of legal hurdles,
-primarily a 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](http://code.google.com/legal/individual-cla-v1.0.html).
-- **If you work for a company that wants to allow you to contribute your work**,
-  then you'll need to sign a [corporate CLA](http://code.google.com/legal/corporate-cla-v1.0.html).
-
-You can sign these electronically (just scroll to the bottom).
-After that, we'll be able to accept your pull requests.