Implement upgrade for Ubuntu provisioner

Signed-off-by: Nathan LeClaire <nathan.leclaire@gmail.com>

libmachine/host.go

@@ -14,6 +14,7 @@ import (
 	"github.com/docker/machine/libmachine/auth"
 	"github.com/docker/machine/libmachine/engine"
 	"github.com/docker/machine/libmachine/provision"
+	"github.com/docker/machine/libmachine/provision/pkgaction"
 	"github.com/docker/machine/libmachine/swarm"
 	"github.com/docker/machine/ssh"
 	"github.com/docker/machine/state"
@@ -221,8 +222,19 @@ func (h *Host) Restart() error {
 }
 
 func (h *Host) Upgrade() error {
-	// TODO: refactor to provisioner
-	return fmt.Errorf("centralized upgrade coming in the provisioner")
+	provisioner, err := provision.DetectProvisioner(h.Driver)
+	if err != nil {
+		return err
+	}
+
+	if err := provisioner.Package("docker", pkgaction.Upgrade); err != nil {
+		return err
+	}
+
+	if err := provisioner.Service("docker", pkgaction.Restart); err != nil {
+		return err
+	}
+	return nil
 }
 
 func (h *Host) Remove(force bool) error {

libmachine/provision/pkgaction/action.go

@@ -27,11 +27,13 @@ type PackageAction int
 const (
 	Install PackageAction = iota
 	Remove
+	Upgrade
 )
 
 var packageActions = []string{
 	"install",
 	"remove",
+	"upgrade",
 }
 
 func (s PackageAction) String() string {

libmachine/provision/ubuntu.go

@@ -56,6 +56,14 @@ func (provisioner *UbuntuProvisioner) Package(name string, action pkgaction.Pack
 		packageAction = "install"
 	case pkgaction.Remove:
 		packageAction = "remove"
+	case pkgaction.Upgrade:
+		packageAction = "upgrade"
+	}
+
+	// TODO: This should probably have a const
+	switch name {
+	case "docker":
+		name = "lxc-docker"
 	}
 
 	command := fmt.Sprintf("DEBIAN_FRONTEND=noninteractive sudo -E apt-get %s -y  %s", packageAction, name)