Set up test environment for webpage

The Post-EOL website needs some dev environment. Eventually, we also want to move the whole website into our k8s-cluster. Insofar,

• docker-ize the current website
• enable auto-deployment into the k8s-cluster for changes to the repository
  • add our existing cluster:
    • certificate
      kubectl --namespace=kommul-dev get secrets default-token-ps174 -o jsonpath="{['data']['ca\.crt']}" | base64 --decode
    • authentication token
      ...from IT