Restore original dockerfile

Dockerfile

@@ -0,0 +1,27 @@
+# LTS Image
+FROM ubuntu:18.04
+
+LABEL maintainer="github.google-sre-ebook@captnemo.in"
+
+ARG DEBIAN_FRONTEND="noninteractive"
+
+COPY . /src/
+
+WORKDIR /src
+
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    build-essential \
+    calibre \
+    pandoc \
+    ruby \
+    ruby-dev \
+    wget \
+    zlib1g-dev \
+    && gem install bundler --no-ri --no-rdoc \
+    && bundle install \
+    && apt-get clean \
+    && rm -rf /var/lib/apt/lists/*
+
+ENTRYPOINT ["/src/bootstrap.sh", "docker"]
+
+VOLUME ["/output"]