doc(releasing.md): add preliminary guide to releasing deis

Author: Aaron Schlesinger

src/contributing/releasing.md

@@ -0,0 +1,21 @@
+# Releasing a New Deis Version
+
+This document describes how to release a new Deis version. It's targetted toward the Deis core
+maintainers.
+
+# Manual Testing
+
+After the chart is created with the immutable Docker image tags that represent the final images
+(i.e. the ones that will be re-tagged to the immutable release tag, such as `2.0.0-beta2`), it
+should be manually tested by as many people as possible. Special attention should be paid to the
+user experience, both from an operator and developer perspective.
+
+Our goal is to test with as many object storage and Kubernetes installation configurations as
+possible, to ensure there are no gaps in configuration or functionality. See below for a testing
+matrix.
+
+Object Storage / Kubernetes Install | Kube-Solo | Google Container Engine | AWS | Micro-Kube | Vagrant |
+----------------------------------- | --------- | ----------------------- | --- | ---------- | ------- |
+Default (Minio)                     |
+Google Cloud Storage                |
+Amazon S3                           |