speed up response by 4x fold

[artofspeed]

Current response time is around 1000ms, because it creates a new socket and close it for every single request. This is too slow for some applications.

I added 1 single line, to use keep-alive, and this cuts the time down to ~250ms.

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[artofspeed]

I signed it!

[googlebot]

CLAs look good, thanks!

[stephenmcd]

Thanks a lot!