Modified connect method so tls.connect options can be supplied.

To connect with tls using certificates, one needs to pass the [options](http://nodejs.org/api/tls.html#tls_tls_connect_port_host_options_callback) such as key, cert, and ca.

I modified the connect method slightly to allow passing those options to tls.connect.

I also modified the listen event to listen for the event 'secureConnect' as defined in the [tls documentation](http://nodejs.org/api/tls.html#tls_event_secureconnect).

I hope you find this useful.  Thanks for the great libraries.