net: add pauseOnConnect option to createServer()

Currently when a server receives a new connection the underlying socket
handle begins reading data immediately. This causes problems when
sockets are passed between processes, as data can be read by the first
process and thus never read by the second process.

This commit allows sockets that are constructed with a handle to be
paused initially.

PR-URL: https://github.com/joyent/node/pull/8576
Fixes: https://github.com/joyent/node/issues/7905
Fixes: https://github.com/joyent/node/issues/7784
Reviewed-by: Trevor Norris <trev.norris@gmail.com>