Docker crontab fixes

Reinstall crontab when container is run in 'daemon' mode.
This is necessary to...
* use a new random minute instead of the one determined at build time
* respect any acme.sh environment variables being passed to the container.

Dockerfile

@@ -58,6 +58,8 @@ RUN for verb in help \
 
 RUN printf "%b" '#!'"/usr/bin/env sh\n \
 if [ \"\$1\" = \"daemon\" ];  then \n \
+ acme.sh --uninstall-cronjob \n \
+ acme.sh --install-cronjob \n \
  trap \"echo stop && killall crond && exit 0\" SIGTERM SIGINT \n \
  crond && while true; do sleep 1; done;\n \
 else \n \