message: Dockerfile: enable sudo
  In order to use this as a base image for the neqo-qns image, we need to
  execute commands as root, both to install additional software as well as
  altering the network configuration. Install sudo and add 'neqo' user
  to sudoers.
diff: @@ -8,7 +8,7 @@ LABEL maintainer="Martin Thomson <mt@lowentropy.net>"
  RUN apt-get update && apt-get install -y --no-install-recommends \
  ca-certificates coreutils curl git make mercurial ssh \
  - build-essential clang llvm libclang-dev gyp ninja-build pkg-config zlib1g-dev \
  + build-essential clang llvm libclang-dev gyp ninja-build pkg-config zlib1g-dev sudo \
  && apt-get autoremove -y && apt-get clean -y \
  && rm -rf /var/lib/apt/lists/*
  @@ -32,6 +32,7 @@ ENV HOME /home/$USER
  ENV SHELL /bin/bash
  RUN useradd -d "$HOME" -s "$SHELL" -m "$USER"
  +RUN echo "$USER ALL=(ALL) NOPASSWD: ALL" >> /etc/sudoers
  WORKDIR $HOME
  USER $USER
  