ref(README): update link to deis graphic

Author: Matthew Fisher

README.md

@@ -6,7 +6,7 @@
 
 Deis (pronounced DAY-iss) Workflow is an open source Platform as a Service (PaaS) that adds a developer-friendly layer to any [Kubernetes](http://kubernetes.io) cluster, making it easy to deploy and manage applications on your own servers.
 
-![Deis Graphic](https://s3-us-west-2.amazonaws.com/get-deis/deis-graphic-small.png)
+![Deis Graphic](https://getdeis.blob.core.windows.net/get-deis/deis-graphic-small.png)
 
 For more information about the Deis Workflow, please visit the main project page at https://github.com/deis/workflow.