Add version output to CLIs

This change adds version output to the nvidia-continer-runtime,
nvidia-container-toolkit, and nvidia-ctk CLIs. The same version
is used in all cases and includes a version string and a git
revision if set.

The construction of the version string mirrors what is done in runc.

Signed-off-by: Evan Lezar <elezar@nvidia.com>

cmd/nvidia-ctk/main.go

@@ -20,12 +20,11 @@ import (
 	"os"
 
 	"github.com/NVIDIA/nvidia-container-toolkit/cmd/nvidia-ctk/hook"
+	"github.com/NVIDIA/nvidia-container-toolkit/internal/info"
 	log "github.com/sirupsen/logrus"
 	cli "github.com/urfave/cli/v2"
 )
 
-var version string
-
 var logger = log.New()
 
 // config defines the options that can be set for the CLI through config files,
@@ -41,10 +40,11 @@ func main() {
 
 	// Create the top-level CLI
 	c := cli.NewApp()
+	c.Name = "NVIDIA Container Toolkit CLI"
 	c.UseShortOptionHandling = true
 	c.EnableBashCompletion = true
 	c.Usage = "Tools to configure the NVIDIA Container Toolkit"
-	c.Version = version
+	c.Version = info.GetVersionString()
 
 	// Setup the flags for this command
 	c.Flags = []cli.Flag{