move hoistDirectives transformer to builtin-setup

src/babel/transformation/transformers/index.js

@@ -1,6 +1,7 @@
 export default {
   //- builtin-setup
   _validation:                             require("./internal/validation"),
+  _hoistDirectives:                        require("./internal/hoist-directives"),
   "utility.removeDebugger":                require("./utility/remove-debugger"),
   "utility.removeConsole":                 require("./utility/remove-console"),
   "utility.inlineEnvironmentVariables":    require("./utility/inline-environment-variables"),
@@ -52,7 +53,6 @@ export default {
   "spec.undefinedToVoid":                  require("./spec/undefined-to-void"),
   jscript:                                 require("./other/jscript"),
   flow:                                    require("./other/flow"),
-  _hoistDirectives:                        require("./internal/hoist-directives"),
 
   //- builtin-advanced
   "es6.destructuring":                     require("./es6/destructuring"),

src/babel/transformation/transformers/internal/hoist-directives.js

@@ -1,5 +1,9 @@
 import * as t from "../../../types";
 
+export var metadata = {
+  group: "builtin-setup"
+};
+
 export var BlockStatement = {
   exit(node) {
     for (var i = 0; i < node.body.length; i++) {