switched to stretch, use entrypoint.sh from release

contrib/docker/Dockerfile

@@ -1,4 +1,4 @@
-FROM debian:jessie
+FROM debian:stretch
 
 RUN apt-get update && apt-get install -y \
     logrotate libmosquitto1 libstdc++6 libc6 libgcc1 \
@@ -30,6 +30,6 @@ RUN rm -rf /build
 
 EXPOSE 8888
 
-COPY runtime/docker-entrypoint.sh /
+COPY release/docker-entrypoint.sh /
 ENTRYPOINT ["/docker-entrypoint.sh"]
 CMD ["-f", "--scanconfig"]