driver/docker: mark cpusets as beta
driver/docker: mark cpusets as beta

The cpuset_cpus flag may be subject to change when we revise cpu
management. Also, it's only available in 1.0.0 Beta.

burdandrei/nomad,dvusboy/nomad,dvusboy/nomad,hashicorp/nomad,hashicorp/nomad,dvusboy/nomad,burdandrei/nomad,burdandrei/nomad,dvusboy/nomad,hashicorp/nomad,burdandrei/nomad,burdandrei/nomad,hashicorp/nomad,hashicorp/nomad,dvusboy/nomad,burdandrei/nomad,dvusboy/nomad,hashicorp/nomad,burdandrei/nomad,dvusboy/nomad