Move --steppath flag to the command step path

Fixes smallstep/step#133

command/path/path.go

@@ -0,0 +1,24 @@
+package path
+
+import (
+	"fmt"
+
+	"github.com/smallstep/cli/command"
+	"github.com/smallstep/cli/config"
+	"github.com/urfave/cli"
+)
+
+func init() {
+	cmd := cli.Command{
+		Name:        "path",
+		Usage:       "print the configured step path and exit",
+		UsageText:   "step path",
+		Description: "**step ca** command prints the configured step path and exit",
+		Action: cli.ActionFunc(func(ctx *cli.Context) error {
+			fmt.Println(config.StepPath())
+			return nil
+		}),
+	}
+
+	command.Register(cmd)
+}