Docker stack deploy labels issue is not easy to read/catch

[jmaitrehenry]

Do you want to request a feature or report a bug?

Bug?

What did you do?

On #1041, a note was added to the documentation, but when you read it here: http://docs.traefik.io/user-guide/swarm-mode/

Note that we set whoami1 to use sticky sessions (--label traefik.backend.loadbalancer.sticky=true). We'll demonstrate that later. If using docker stack deploy, there is a specific way that the labels must be defined in the docker-compose file.

And you don't have a sticky need, you will not read the rest of the line, but the problem with docker stack deploy is on the same line

What did you expect to see?

Two notes or two lines

I will made a PR in a few minutes with a fix.