var transporter = nodemailer.createTransport({
  service:"Mailjet", // sets automatically host, port and connection security settings
    auth: {
    user:'******',
    pass:'*******'
  }
});
var mailOptions = {
  to:mailTo,
  from:'******',
  subject:'user registered',
  text:'welcome user'
};
transporter.sendMail(mailOptions, function(err, info) {
  if (err) {
    logger.debug('error in sending email ' + err);
  } else {
    logger.debug('Message sent: ' + info.response);
  };