makeDockerClusterPSOCK: Make the Docker cluster on Google Compute Engine
In cloudyr/googleComputeEngineR: R Interface with Google Compute Engine

Called by as.cluster

makeDockerClusterPSOCK(
  workers,
  docker_image = "rocker/r-parallel",
  rscript = c("docker", "run", "--net=host", docker_image, "Rscript"),
  rscript_args = NULL,
  install_future = FALSE,
  ...,
  verbose = FALSE
)

`workers`	The VMs being called upon
`docker_image`	The docker image to use on the cluster
`rscript`	The Rscript command to run on the cluster
`rscript_args`	Arguments to the RScript
`install_future`	Whether to check if future is installed first (not needed if using docker derived from rocker/r-parallel which is recommended)
`...`	Other arguments passed to makeClusterPSOCK
`verbose`	How much feedback to show