code: function mkdir() {
  		fs.existsSync(build_path) || fs.mkdirSync(build_path);
  		fs.existsSync(path_main) || fs.mkdirSync(path_main);
  		fs.existsSync(path_min) ? util.cleardir(path_min) : fs.mkdirSync(path_min);
  		fs.existsSync(path_updated) || fs.mkdirSync(path_updated);
  	}
docs: 创建构建目录