NPM镜像代理设置
用户目录C:\Users\xxx下建立.npmrc文件，内容如下：
registry="https://registry.npm.taobao.org"
ELECTRON_MIRROR="https://npm.taobao.org/mirrors/electron/"
SASS_BINARY_SITE="https://npm.taobao.org/mirrors/node-sass"
用户目录C:\Users\xxx下建立.npmrc文件，内容如下：
registry="https://registry.npm.taobao.org"
ELECTRON_MIRROR="https://npm.taobao.org/mirrors/electron/"
SASS_BINARY_SITE="https://npm.taobao.org/mirrors/node-sass"