查看vuejs-demo，引入的外部链接js、css，那如何引入本地文件？
import fromCDN from "from-cdn"; export default { name:'chart', created:function(){ this.ready = fromCDN([ "//cdn.dhtmlx.com/5.1/dhtmlx.js", "//cdn.dhtmlx.com/5.1/dhtmlx.css" ]); }, mounted:function(){ this.ready.then(() => { var chart = new dhtmlXChart({