安装完yarn后同理也要设置镜像源：
yarn config set registry https://registry.npm.taobao.org --global
执行命令出现:
usr/bin/env: "node": 没有那个文件或目录
解决办法
https://stackoverflow.com/questions/18130164/nodejs-vs-node-on-ubuntu-12-04
You need to manually create a symlink /usr/bin/node. Shortcut for bash compatible shells:
sudo ln -s which nodejs /usr/bin/node
Or if you use non-standard shells, just hardcode the path you find with which nodejs:
sudo ln -s /usr/bin/nodejs /usr/bin/node
