Remove Kubernetes.md and update README to point to kubernetes-engine-samples repo instead
Remove Kubernetes.md and update README to point to kubernetes-engine-samples repo instead

Kubernetes.md set up the proxy as a service. This required opening up IP access on 0.0.0.0, which posed a security risk. The kubernetes-engine-samples repo configures the proxy in the sidecar pod configuration, which is the best way to go.
GoogleCloudPlatform/cloud-sql-proxy,GoogleCloudPlatform/cloud-sql-proxy