Configring node js.

node_modules/core-js/library/modules/es7.string.trim-left.js

@@ -0,0 +1,7 @@
+'use strict';
+// https://github.com/sebmarkbage/ecmascript-string-left-right-trim
+require('./_string-trim')('trimLeft', function($trim){
+  return function trimLeft(){
+    return $trim(this, 1);
+  };
+}, 'trimStart');