Add support for NTLM the WinRM communicator.

WinRM exposes an HTTP transport decorator that can be used for different
authentication schemes.  Windows on Azures requires this if one is to use
the out of the box configuration.

Godeps/Godeps.json

@@ -329,7 +329,7 @@
 		},
 		{
 			"ImportPath": "github.com/packer-community/winrmcp/winrmcp",
-			"Rev": "3d184cea22ee1c41ec1697e0d830ff0c78f7ea97"
+			"Rev": "f1bcf36a69fa2945e65dd099eee11b560fbd3346"
 		},
 		{
 			"ImportPath": "github.com/pierrec/lz4",

communicator/winrm/communicator.go

@@ -41,6 +41,11 @@ func New(config *Config) (*Communicator, error) {
 
 	// Create the client
 	params := winrm.DefaultParameters()
+
+	if config.TransportDecorator != nil {
+		params.TransportDecorator = config.TransportDecorator
+	}
+
 	params.Timeout = formatDuration(config.Timeout)
 	client, err := winrm.NewClientWithParameters(
 		endpoint, config.Username, config.Password, params)
@@ -155,5 +160,6 @@ func (c *Communicator) newCopyClient() (*winrmcp.Winrmcp, error) {
 		Insecure:              c.config.Insecure,
 		OperationTimeout:      c.config.Timeout,
 		MaxOperationsPerShell: 15, // lowest common denominator
+		TransportDecorator:    c.config.TransportDecorator,
 	})
 }

communicator/winrm/config.go

@@ -1,6 +1,7 @@
 package winrm
 
 import (
+	"net/http"
 	"time"
 )
 
@@ -13,4 +14,5 @@ type Config struct {
 	Timeout            time.Duration
 	Https              bool
 	Insecure           bool
+	TransportDecorator func(*http.Transport) http.RoundTripper
 }

helper/communicator/config.go

@@ -3,6 +3,7 @@ package communicator
 import (
 	"errors"
 	"fmt"
+	"net/http"
 	"os"
 	"time"
 
@@ -39,6 +40,7 @@ type Config struct {
 	WinRMTimeout            time.Duration `mapstructure:"winrm_timeout"`
 	WinRMUseSSL             bool          `mapstructure:"winrm_use_ssl"`
 	WinRMInsecure           bool          `mapstructure:"winrm_insecure"`
+	WinRMTransportDecorator func(*http.Transport) http.RoundTripper
 }
 
 // Port returns the port that will be used for access based on config.

helper/communicator/step_connect_winrm.go

@@ -131,6 +131,7 @@ func (s *StepConnectWinRM) waitForWinRM(state multistep.StateBag, cancel <-chan
 			Timeout:            s.Config.WinRMTimeout,
 			Https:              s.Config.WinRMUseSSL,
 			Insecure:           s.Config.WinRMInsecure,
+			TransportDecorator: s.Config.WinRMTransportDecorator,
 		})
 		if err != nil {
 			log.Printf("[ERROR] WinRM connection err: %s", err)