README.md: Add a reference for API conventions
* README.md: Add a section on defining new APIs, with a reference to the
API conventions section of the OpenShift CONVENTIONS.md document.
# api
The canonical location of the OpenShift API definition. This repo holds the API type definitions and serialization code used by [openshift/client-go](https://github.com/openshift/client-go)
+## defining new APIs
+
+When defining a new API, please follow [the OpenShift API
+conventions](https://github.com/openshift/enhancements/blob/master/CONVENTIONS.md#api),
+and then follow the instructions below to regenerate CRDs (if necessary) and
+submit a pull request with your new API definitions and generated files.
+
## pull request process
Pull requests that change API types in this repo that have corresponding "internal" API objects in the
