Update structure

pleroma.dockerfile

@@ -1,12 +1,25 @@
 FROM elixir:1.6-alpine
 
-RUN apk add --no-cache --virtual .build alpine-sdk git
+WORKDIR /pleroma
 
+# Prepare system
+RUN apk add --no-cache --virtual .build alpine-sdk git rsync
+
+# Perform a clone that can be cached
+RUN git clone https://git.pleroma.social/pleroma/pleroma.git .
+
+# Prepare pleroma
 ADD ./docker-config.exs /docker-config.exs
+ARG PLEROMA_VERSION
+RUN \
+    git checkout $PLEROMA_VERSION && \
+    git pull --rebase --autostash && \
+    ln -s /docker-config.exs config/prod.secret.exs && \
+    ln -s /docker-config.exs config/dev.secret.exs
 
+# Register entrypoint
 ADD ./entrypoint.ash /
 RUN chmod +x /entrypoint.ash
-ENTRYPOINT ["/entrypoint.ash"]
-CMD ["run"]
+CMD ["/entrypoint.ash"]
 
 EXPOSE 4000