Add command to generate man pages

The climan package has a command that can be registered with any urfav
cli app to generate man pages.

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>

cmd/containerd-stress/main.go

@@ -30,6 +30,7 @@ import (
 
 	"github.com/containerd/containerd"
 	"github.com/containerd/containerd/namespaces"
+	"github.com/containerd/containerd/pkg/climan"
 	"github.com/containerd/containerd/plugin"
 	metrics "github.com/docker/go-metrics"
 	"github.com/sirupsen/logrus"
@@ -161,6 +162,7 @@ func main() {
 	}
 	app.Commands = []cli.Command{
 		densityCommand,
+		climan.Command,
 	}
 	app.Action = func(context *cli.Context) error {
 		config := config{