npm yarn nvm 更换镜像 以及配置scss镜像解决scss安装失败

yarn 
查看配置
yarn config get registry
安装
npm install -g yarn --registry=https://registry.npm.taobao.org
配置镜像
yarn config set registry https://registry.npm.taobao.org -g
yarn config set sass_binary_site http://cdn.npm.taobao.org/dist/node-sass -g
npm 

查看配置
npm get registry 
配置镜像
npm config set registry http://registry.npm.taobao.org/
npm config set sass-binary-site http://npm.taobao.org/mirrors/node-sass

nvm 
配置镜像
node_mirror: https://npm.taobao.org/mirrors/node/
npm_mirror: https://npm.taobao.org/mirrors/npm/