doc: add CONTRIBUTING.md file
Change-Id: I0186ccf72b8a919456ff5d43ee3302395a6c7358
Reviewed-on: https://go-review.googlesource.com/20312
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
new file mode 100644
index 0000000..ff54c47
--- /dev/null
+++ b/CONTRIBUTING.md
@@ -0,0 +1,18 @@
+# Contributing to godoc.org
+
+**We do not accept GitHub pull requests**
+(we use [Gerrit](https://code.google.com/p/gerrit/) instead for code review).
+
+To get started contributing to this project,
+clone the repository from its canonical location
+
+ git clone https://go.googlesource.com/gddo
+
+or update the `origin` of your existing clone
+
+ git remote rm origin
+ git remote add origin https://go.googlesource.com/gddo
+
+then read the [Contribution Guidelines](https://golang.org/doc/contribute.html)
+to learn how to send patches using Gerrit.
+
