Updated code to use 'net' rather than 'http' for TCP connection

It looks like the code continued to use the http module when it was changed to use Logentries TCP token input instead of the HTTP PUT input.

I noticed there was an issue when a simple program with a log statement in it would not terminate. It looks like the http connection was not being torn down when end was called on the transport.

I've changed the transport to use the net module and write directly to the TCP socket. The end method in the transport should now tear down the connection.