setup grub serial settings if ttyS0

Signed-off-by: Jeff Carr <jcarr@wit.com>

window-main.go

@@ -88,6 +88,9 @@ func mainTab(n *gui.Node) {
 		doCmd("cat /etc/init.d/ttyS0")
 		doCmd("systemctl enable serial-getty@ttyS0.service")
 		doCmd("service serial-getty@ttyS0 start")
+		grub, _ := res.ReadFile("grub.d/wit.cfg")
+		ioutil.WriteFile("/etc/default/grub.d/wit.cfg", grub, 0644)
+		doCmd("update-grub")
 		os.Exit(0)
 	})
 	rn.NewButton("git config", func () {