Update contributors doc (facebookarchive#1009)

flarnie · web-flow · commit b076d7ba15b7 · 2017-02-14T13:23:24.000-08:00
* Add Code of Conduct to CONTRIBUTING doc Good stuff. Snagged from the [React 'How to Contribute'](https://facebook.github.io/react/contributing/how-to-contribute.html) page. * Add stability philosophy to CONTRIBUTING doc To address questions and concerns we have had internally and externally about API changes. * Fix missing newline Thanks to @existentialism for catching this.
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
@@ -2,6 +2,11 @@
 We want to make contributing to this project as easy and transparent as
 possible.
 
+## Code of Conduct 
+Facebook has adopted a Code of Conduct that we expect project
+participants to adhere to. Please [read the full text](https://code.facebook.com/codeofconduct)
+so that you can understand what actions will and will not be tolerated.
+
 ## Our Development Process
 We use GitHub to sync code to and from our internal repository. We'll use GitHub
 to track issues and feature requests, as well as accept pull requests.
@@ -37,6 +42,18 @@ outlined on that page and do not file a public issue.
 * 80 character line length
 * Run `npm run lint` to conform to our lint rules
 
+## Stability
+Our philosophy regarding API changes is as follows:
+ * We will avoid changing APIs and core behaviors in general
+ * In order to avoid stagnation we will allow for API changes in cases where
+ there is no other way to achieve a high priority bug fix or improvement.
+ * When there is an API change:
+    * Changes will have a clearly documented reason and migration path
+    * When deprecating a pattern, these steps will be followed:
+        * We will test the change internally first at FB
+        * A version will be released that supports both, with deprecation warnings
+        * The following version will fully remove the deprecated pattern
+
 ## License
 By contributing to Draft.js, you agree that your contributions will be licensed
 under its BSD license.
