Document exposing ports in Dockerfile

Dockerfile

@@ -8,7 +8,9 @@
 # This Dockerfile is hardcoded to run the websockets server at
 # port 8000.
 # Start the docker container with
-# docker run -it -p 8000:8000 consoledemo
+# docker run -it -p 8000:8000 -p 11031:11031 -p 11030:11030 -p 11040:11040 -p 11041:11041 -p 11042:11042 -p 11011:11011 consoledemo
+# The ports in the 11000 range are for accessing the console with scripts,
+# e.g. with the python Telescope class.
 # Then visit the consoledemo from the host machine at http://localhost:8000 
 FROM debian:buster AS builder