remove polyfill from main package

packages/babel-core/polyfill.js

@@ -1,2 +0,0 @@
-console.trace('The use of `require("babel/polyfill") is deprecated. Please us require("babel-polyfill")');
-module.exports = require("babel-polyfill");

packages/babel-core/src/api/node.js

@@ -30,15 +30,6 @@ export function register(opts?: Object) {
   return callback;
 }
 
-/**
- * Register polyfill globally.
- */
-
-export function polyfill() {
-  console.trace('The use of `require("babel").polyfill() is deprecated. Please us require("babel-polyfill")');
-  require("babel-polyfill");
-}
-
 /**
  * Asynchronously transform `filename` with optional `opts`, calls `callback` when complete.
  */