polkadot builds (gitlab), releases (docker) and deployment (kubernetes) (#48)

* ci: add Dockerfile and its build

* make docker version tag

* polkadot with static ip address in nodeport stateful set on kubernetes

* use helm for templating

* enable rbac for polkadot

polkadot/scripts/kubernetes/README.md

@@ -0,0 +1,47 @@
+
+
+# Polkadot Kubernetes Helm Chart
+
+This [Helm Chart](https://helm.sh/) can be used for deploying containerized 
+**Polkadot** to a [Kubernetes](https://kubernetes.io/) cluster.
+
+
+## Prerequisites
+
+- Tested on Kubernetes 1.10.7-gke.6
+
+## Installation
+
+To install the chart with the release name `my-release` into namespace 
+`my-namespace` from within this directory:
+
+```console
+$ helm install --namespace my-namespace --name my-release --values values.yaml ./
+```
+
+The command deploys Polkadot on the Kubernetes cluster in the configuration 
+given in `values.yaml`. When the namespace is omitted it'll be installed in 
+the default one.
+
+
+## Removal of the Chart
+
+To uninstall/delete the `my-release` deployment:
+
+```console
+$ helm delete --namespace my-namespace my-release
+```
+
+The command removes all the Kubernetes components associated with the chart and deletes the release.
+
+
+## Upgrading
+
+Once the chart is installed and a new version should be deployed helm takes 
+care of this by
+
+```console
+$ helm upgrade --namespace my-namespace --values values.yaml my-release ./
+```
+
+