Need to change from executor docker mode to shell mode

Commonly Users want to use docker in their pipelines. If so, then since the runner is running in a docker container, we get into the docker-in-docker situation.

Bit dated but a good read why to avoid docker in docker: https://jpetazzo.github.io/2015/09/03/do-not-use-docker-in-docker-for-ci/

UPDATE: Make this a variable for input on what type of executor we run