fix passing bootstrap_args to bootstrap script

provisioner/salt-masterless/provisioner.go

@@ -114,7 +114,14 @@ func (p *Provisioner) Provision(ui packer.Ui, comm packer.Communicator) error {
 	ui.Say("Provisioning with Salt...")
 	if !p.config.SkipBootstrap {
 		cmd := &packer.RemoteCmd{
-			Command: fmt.Sprintf("wget -O - https://bootstrap.saltstack.com | sudo sh -s %s", p.config.BootstrapArgs),
+			Command: fmt.Sprintf("curl -L https://bootstrap.saltstack.com -o /tmp/install_salt.sh"),
+		}
+		ui.Message(fmt.Sprintf("Downloading saltstack bootstrap to /tmp/install_salt.sh"))
+		if err = cmd.StartWithUi(comm, ui); err != nil {
+			return fmt.Errorf("Unable to download Salt: %d", err)
+		}
+		cmd = &packer.RemoteCmd{
+			Command: fmt.Sprintf("sudo sh /tmp/install_salt.sh %s", p.config.BootstrapArgs),
 		}
 		ui.Message(fmt.Sprintf("Installing Salt with command %s", cmd))
 		if err = cmd.StartWithUi(comm, ui); err != nil {