remove docker-in-docker - use volumes

Dockerfile

@@ -1,12 +1,9 @@
 FROM library/alpine:3.5
 
 ENV HOME_DIR=/opt/crontab
-RUN apk add --no-cache --virtual .run-deps bash curl jq docker \
+RUN apk add --no-cache --virtual .run-deps bash curl jq \
     && mkdir -p ${HOME_DIR}
 
-# Dev
-#COPY config.json ${HOME_DIR}/
-
 COPY docker-entrypoint /
 ENTRYPOINT ["/docker-entrypoint"]