Convenience script call updated

- use curl for consistency
- copied the warning from the install script (i.e., do not use for prod
  envs)

docs/operators/tutorial.md

@@ -36,7 +36,8 @@ Otherwise, here are the step required:
 ssh <server-domain>
 
 # docker install convenience script
-wget -O- https://get.docker.com | bash
+# not suitable for production environments - refer to the script header for alternatives
+curl https://get.docker.com | bash
 
 # check that docker was installed correctly
 sudo docker run hello-world