Restrict container from acquiring additional privileges 

As per this PR: https://github.com/docker/docker/pull/20727
I tried testing `docker run -it --rm --security-opt=no-new-privileges fedora bash` but it fails: `Error response from daemon: Invalid --security-opt: "no-new-privileges"`
