anchor.diff:  #   https://engineering.riotgames.com/news/jenkins-docker-proxies-and-compose
   
   FROM jenkins/jenkins:2.130
  +
  +LABEL maintainer "Marcin Grzejszczak <mgrzejszczak@pivotal.io>"
  +
  +SHELL ["/bin/bash", "-o", "pipefail", "-c"]
  +
  +ENV DEBIAN_FRONTEND=noninteractive
  +ENV ANSIBLE_VERSION 2.6.3
  +ENV JAVA_OPTS -Djenkins.install.runSetupWizard=false \
  +              -Djava.awt.headless=true \
  +              -Dhudson.model.ParametersAction.keepUndefinedParameters=true \
  +              -Dpermissive-script-security.enabled=no_security
  +
   ARG gituser=changeme
   ARG gitpass=changeme
   ARG gitsshkey=
  
positive.code: ARG dockerRegistryUser=changeme
  ARG dockerRegistryPass=changeme
  ARG dockerRegistryEmail=changeme
  
  MAINTAINER Marcin Grzejszczak <mgrzejszczak@pivotal.io>
  
  COPY seed/init.groovy /usr/share/jenkins/ref/init.groovy
  COPY seed/jenkins_pipeline.groovy /usr/share/jenkins/jenkins_pipeline.groovy
  
negative.code: 
  # Generated via `start.sh`. If you don't want to provide it just put empty
  # files there
  RUN echo -n "${gituser}" > /usr/share/jenkins/gituser && \
      echo -n "${gitpass}" > /usr/share/jenkins/gitpass && \
      echo -n "${gitsshkey}" > /usr/share/jenkins/gitsshkey && \
      echo -n "${dockerRegistryUser}" > /usr/share/jenkins/dockerRegistryUser && \
      echo -n "${dockerRegistryPass}" > /usr/share/jenkins/dockerRegistryPass && \
      echo -n "${dockerRegistryEmail}" > /usr/share/jenkins/dockerRegistryEmail && \
      chmod 400 /usr/share/jenkins/gitsshkey
  
  # Default mysql credentials - you can modify them as you please. You can
  # parametrize them so that values are not hardcoded
  RUN echo -n rootpassword > /usr/share/jenkins/mySqlRootPass && \
      echo -n username > /usr/share/jenkins/mySqlPass && \
      echo -n password > /usr/share/jenkins/mySqlUser
  
  # Install tools needed by the master worker for building apps
  RUN apt-get update && \
      apt-get install -y --no-install-recommends ruby curl jq apt-transport-https ca-certificates && \
      apt-get clean && \
      rm -rf /var/lib/apt/lists/*
  
  # Install cf-cli
  RUN curl -sL https://packages.cloudfoundry.org/debian/cli.cloudfoundry.org.key | apt-key add - && \
      echo "deb http://packages.cloudfoundry.org/debian stable main" | tee /etc/apt/sources.list.d/cloudfoundry-cli.list && \
      apt-get update && \
      apt-get install -y --no-install-recommends cf-cli && \
      apt-get clean && \
      rm -rf /var/lib/apt/lists/*
  
  # Install kubectl
  RUN KUBERNETES_VERSION="$( curl -s https://storage.googleapis.com/kubernetes-release/release/stable.txt )" && \
      curl -o /usr/local/bin/kubectl -LO "https://storage.googleapis.com/kubernetes-release/release/${KUBERNETES_VERSION}/bin/linux/amd64/kubectl" && \
      chmod 755 /usr/local/bin/kubectl
  
  # Install Ansible
  RUN apt-get update && \
      apt-get install -y --no-install-recommends python-dev python-pip python-setuptools && \
      pip install --no-cache-dir ansible==${ANSIBLE_VERSION} && \
      apt-get clean && \
      rm -rf /var/lib/apt/lists/*
  
  # Making docker in docker possible
  RUN echo "deb https://apt.dockerproject.org/repo debian-jessie main" | tee /etc/apt/sources.list.d/docker.list && \
      apt-key adv --keyserver hkp://p80.pool.sks-keyservers.net:80 --recv-keys 58118E89F3A912897C070ADBF76221572C52609D && \
      apt-get update && \
      apt-get install -y --no-install-recommends docker-engine && \
      echo "jenkins ALL=NOPASSWD: /usr/bin/docker" >> /etc/sudoers && \
      echo "jenkins ALL=NOPASSWD: /usr/local/bin/docker-compose" >> /etc/sudoers && \
      echo 'Defaults  env_keep += "HOME"' >> /etc/sudoers && \
      apt-get clean && \
      rm -rf /var/lib/apt/lists/*
  
  # You can use Jenkins API to generate the list of plugins from a running
  # Jenkins instance:
  