Bump libcompose and sync dependencies

vendor/github.com/godbus/dbus/auth_external.go

@@ -1,26 +0,0 @@
-package dbus
-
-import (
-	"encoding/hex"
-)
-
-// AuthExternal returns an Auth that authenticates as the given user with the
-// EXTERNAL mechanism.
-func AuthExternal(user string) Auth {
-	return authExternal{user}
-}
-
-// AuthExternal implements the EXTERNAL authentication mechanism.
-type authExternal struct {
-	user string
-}
-
-func (a authExternal) FirstData() ([]byte, []byte, AuthStatus) {
-	b := make([]byte, 2*len(a.user))
-	hex.Encode(b, []byte(a.user))
-	return []byte("EXTERNAL"), b, AuthOk
-}
-
-func (a authExternal) HandleData(b []byte) ([]byte, AuthStatus) {
-	return nil, AuthError
-}