Documentation: recommended config when running docker on OSX
If you're going to evaluate gitlab-ci on a docker stack on OSX then you should probably use the config container method. Otherwise the gitlab-runner config doesn't persist past the docker vm restarting. If you're new to docker that's not obvious and you have no idea why your runners keep disappearing. It might also help to make clear that with the other method the mounted volumes are on the docker vm and not the local system hosting the docker vm.