Set a TCP keep alive on the socket to prevent silent timeouts on Azure

The current implementation of winston-papertrail is unfirtunately not working when running on a VM on Azure. The specifics of the Azure network requires sockets to send a keepalive, or the connection is silently dropped after 4 minutes of inactivity. This patch changes the way the stream to papertrail is set up and sets a TCP keep alive on the TCP socket.