基于vue cli创建一个vue项目
首先安装最新的vue cli脚手架，
npm install --global @vue/cli
npm WARN optional SKIPPING OPTIONAL DEPENDENCY: fsevents@1.2.13 (node_modules\@vue\cli\node_modules\fsevents): npm WARN notsup SKIPPING OPTIONAL DEPENDENCY: Unsupported platform for fsevents@1.2.13: wanted {"os":"darwin","arch":"any"} (current: {"os":"win32","arch":"x64"}) + @vue/cli@4.4.6 added 1230 packages from 670 contributors in 118.122s
