Revert "Mount cgroups in the container"

This reverts commit b441dfa7293dfff89efb81800ba968ed73f8f0d1.

Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@docker.com> (github: crosbymichael)
Merge pull request #30 from crosbymichael/revert-mount-cgroup

Revert "Mount cgroups in the container"