Fix docker::image to not run images

[hugotanure]

According the documentation, the resource docker::image should just to pull an image, not properly try to run.

To install a Docker image, add the docker::image defined type to the manifest file:

docker::image { 'base': }
The code above is equivalent to running the docker pull base command. However, it removes the default five-minute execution timeout.

[davejrt]

LGTM