Like request has proxy option https://github.com/request/request#proxies, it is extremely useful for Chinese developers who use vpn to access google api

I actually opened a related issue #1471 but it was closed.

I raised a question at stackoverflow https://stackoverflow.com/questions/53593182/client-network-socket-disconnected-before-secure-tls-connection-was-established

But I think if api can support proxy option, it will be easiest solution.