Add MQTT IP parm

Change-Id: I19ad078ede11f097b0536eedd0ea18f6f252f23d
diff --git a/docker/Dockerfile b/docker/Dockerfile
index f117a09..b9b88b5 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -22,4 +22,4 @@
 
 RUN pip3 install -r requirements.txt
 
-CMD ["./bin/person_detection.sh"]
+ENTRYPOINT ["./bin/person_detection.sh"]