This was mostly done automatically and then visually inspected for obvious errors.
All //-style comments should have a 2-space separation from the code, and 1 space after the comment sign.
Only the client can decide that the connection can be kept alive, we must close the socket if the client doesn't indicate keepalive support.
This will provide a fix for #390 when #560 is fixed; until then the issue remains, just it's no longer HTTPServer's fault.