add register-without-polyfill option

src/babel/api/node.js

@@ -17,7 +17,7 @@ import * as t from "../types";
 export { t as types };
 
 export function register(opts?: Object) {
-  var callback = require("./register/node");
+  var callback = require("./register/node-polyfill");
   if (opts != null) callback(opts);
   return callback;
 }

src/babel/api/register/node-polyfill.js

@@ -0,0 +1,2 @@
+import "../../polyfill";
+export { default } from "./node";

src/babel/api/register/node.js

@@ -1,4 +1,3 @@
-import "../../polyfill";
 import sourceMapSupport from "source-map-support";
 import * as registerCache from "./cache";
 import resolveRc from "../../tools/resolve-rc";