message: split up the varnish vmod build.
diff: ARG IMAGE_REPO
  FROM ${IMAGE_REPO:-lagoon}/commons as commons
  +
  +
  +FROM alpine:3.7 as vmod
  +
  +ENV VERSION=5.2
  +RUN apk --no-cache add varnish varnish-dev automake autoconf libtool python py-docutils make
  +RUN cd /tmp && wget https://github.com/nigoroll/libvmod-dynamic/archive/${VERSION}.zip && \
  + unzip ${VERSION}.zip && cd libvmod-dynamic-${VERSION} && \
  + ./autogen.sh && ./configure && make && make install
  +
  FROM alpine:3.7
  LABEL maintainer="amazee.io"
  @@ -19,7 +29,7 @@ ENV TMPDIR=/tmp \
  # When Bash is invoked as non-interactive (like `bash -c command`) it sources a file that is given in `BASH_ENV`
  BASH_ENV=/home/.bashrc
  -RUN apk --no-cache add varnish varnish-dev automake autoconf libtool python py-docutils make
  +RUN apk --no-cache add varnish
  RUN echo "${VARNISH_SECRET:-lagoon_default_secret}" >> /etc/varnish/secret
  @@ -32,12 +42,7 @@ RUN fix-permissions /etc/varnish/ \
  COPY docker-entrypoint /lagoon/entrypoints/70-varnish-entrypoint
  -ENV VERSION=5.2
  -
  -RUN cd /tmp && wget https://github.com/nigoroll/libvmod-dynamic/archive/${VERSION}.zip && \
  - unzip ${VERSION}.zip && cd libvmod-dynamic-${VERSION} && \
  - ./autogen.sh && ./configure && make && make install && \
  - cd / && rm -Rf libvmod-dynamic-${VERSION}
  +COPY --from=vmod /usr/lib/varnish/vmods/libvmod_dynamic.* /usr/lib/varnish/vmods/
  EXPOSE 8080
  