cli: add help for 'ui -authenticate' flag
cli: add help for 'ui -authenticate' flag

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