nodejs https request CERT_UNTRUSTED

当nodejs 调用不受信任的https 的时候 会返回
CERT_UNTRUSTED 错误，如要解决，需要在调用request 前执行如下代码：

process.env.NODE_TLS_REJECT_UNAUTHORIZED = "0";

参考文章：
http://stackoverflow.com/questions/10888610/ignore-invalid-self-signed-ssl-certificate-in-node-js-with-https-request