linux package build: use stack lts-9.

Also break up the build into three chunks for better
cacheability.

linux/Dockerfile

@@ -7,15 +7,32 @@ RUN apk update
 RUN apk add alpine-sdk git ca-certificates ghc cabal stack zlib-dev \
     dpkg fakeroot sed gawk grep bash linux-headers
 RUN stack update
-RUN stack upgrade
-RUN $HOME/.local/bin/stack config set system-ghc --global true
+RUN stack config set system-ghc --global true
 #RUN mkdir -p /etc/stack
 #RUN echo "build: { split-objs: true }" > /etc/stack/config.yaml
 RUN mkdir -p /usr/src/
 WORKDIR /usr/src/
-RUN git clone https://github.com/jgm/pandoc
+RUN git  clone https://github.com/jgm/pandoc
 WORKDIR /usr/src/pandoc
-RUN $HOME/.local/bin/stack install --compiler 'ghc-8.0.2' \
+RUN stack install --stack-yaml stack.lts9.yaml \
+    --only-dependencies \
+    --flag 'pandoc:static' \
+    --flag 'pandoc:embed_data_files' \
+    --flag 'pandoc-citeproc:static' \
+    --flag 'pandoc-citeproc:embed_data_files' \
+    --flag 'hslua:-export-dynamic' \
+    --ghc-options '-O2 -optc-Os -optl=-pthread -optl=-static -fPIC' \
+    aeson
+RUN stack install --stack-yaml stack.lts9.yaml \
+    --only-dependencies \
+    --flag 'pandoc:static' \
+    --flag 'pandoc:embed_data_files' \
+    --flag 'pandoc-citeproc:static' \
+    --flag 'pandoc-citeproc:embed_data_files' \
+    --flag 'hslua:-export-dynamic' \
+    --ghc-options '-O2 -optc-Os -optl=-pthread -optl=-static -fPIC' \
+    http-client-tls
+RUN stack install --stack-yaml stack.lts9.yaml \
     --only-dependencies \
     --flag 'pandoc:static' \
     --flag 'pandoc:embed_data_files' \
@@ -26,7 +43,7 @@ RUN $HOME/.local/bin/stack install --compiler 'ghc-8.0.2' \
     pandoc pandoc-citeproc
 CMD git pull && \
     git checkout -b work $TREE && \
-    $HOME/.local/bin/stack install --compiler 'ghc-8.0.2' \
+    stack install --stack-yaml stack.lts9.yaml \
       --flag 'pandoc:static' \
       --flag 'pandoc:embed_data_files' \
       --flag 'pandoc-citeproc:static' \