Prepare pandoc upgrade (not pushed to docker hub yet)

Makefile

@@ -62,7 +62,6 @@ export-example:
 
 docker:
 	cd build && docker build -t strongdm/pandoc .
-	docker tag jagregory/pandoc:latest strongdm/pandoc:latest
 	docker push strongdm/pandoc
 
 cleanse:

build/Dockerfile

@@ -1,3 +1,28 @@
-FROM scratch
+FROM haskell:latest
 
-MAINTAINER strongDM Comply <comply@strongdm.com>
+# based on implementation by James Gregory <james@jagregory.com>
+MAINTAINER Comply <comply@strongdm.com>
+
+# install latex packages
+RUN apt-get update -y \
+  && apt-get install -y -o Acquire::Retries=10 --no-install-recommends \
+    texlive-latex-base \
+    texlive-xetex \
+    latex-xcolor \
+    texlive-latex-extra \
+    fontconfig \
+    unzip \
+    lmodern
+
+# will ease up the update process
+# updating this env variable will trigger the automatic build of the Docker image
+ENV PANDOC_VERSION "2.2.1"
+
+# install pandoc
+RUN cabal update && cabal install pandoc-${PANDOC_VERSION}
+
+WORKDIR /source
+
+ENTRYPOINT ["/root/.cabal/bin/pandoc"]
+
+CMD ["--help"]