anchor.diff:  RUN useradd -p testbot testbot
   RUN mkdir -p /home/testbot
   RUN chown testbot /home/testbot
  +
  +# install chrome
  +ENV CHROME_VERSION stable
  +RUN /tmp/install-chrome.sh
  
positive.code: # install packages
  RUN apt-get install -y nodejs git xvfb build-essential git
  
  # install chrome
  RUN /tmp/install-chrome.sh
  
  # configure video loopback
  RUN /tmp/setup-loopbackvideo.sh
  
  
negative.code: FROM ubuntu:14.04
  MAINTAINER Damon Oehlman <damon.oehlman@nicta.com.au>
  
  # add resources
  ADD ./resource/scripts/ /tmp/
  
  # use aarnet mirror for quicker building while developing
  RUN sed -i 's/archive.ubuntu.com/mirror.aarnet.edu.au\/pub\/ubuntu\/archive/g' /etc/apt/sources.list
  
  # install wget and curl
  RUN apt-get -y update
  