adding support for --bundle -b to start, restore, and spec; fixes issue #310

Signed-off-by: Mike Brown <brownwm@us.ibm.com>

start.go

@@ -22,18 +22,19 @@ var startCommand = cli.Command{
 	Usage: "create and run a container",
 	Flags: []cli.Flag{
 		cli.StringFlag{
-			Name:  "config-file, c",
-			Value: "config.json",
-			Usage: "path to spec config file",
-		},
-		cli.StringFlag{
-			Name:  "runtime-file, r",
-			Value: "runtime.json",
-			Usage: "path to runtime config file",
+			Name:  "bundle, b",
+			Value: "",
+			Usage: "path to the root of the bundle directory",
 		},
 	},
 	Action: func(context *cli.Context) {
-		spec, rspec, err := loadSpec(context.String("config-file"), context.String("runtime-file"))
+		bundle := context.String("bundle")
+		if bundle != "" {
+			if err := os.Chdir(bundle); err != nil {
+				fatal(err)
+			}
+		}
+		spec, rspec, err := loadSpec(specConfig, runtimeConfig)
 		if err != nil {
 			fatal(err)
 		}