SmtpConfig
constructor(host: String, port: Int = SmtpSecurity.STARTTLS.defaultPort, security: SmtpSecurity = SmtpSecurity.STARTTLS, auth: SmtpAuth? = null, clientHostname: String = "localhost", connectTimeout: Duration = 30.seconds, commandTimeout: Duration = 5.minutes, dataTimeout: Duration = 10.minutes, maxConnections: Int = 1, reuseConnections: Boolean = true, failOnRejectedRecipient: Boolean = true, allowInsecureAuth: Boolean = false, socketFactory: SmtpSocketFactory = defaultSmtpSocketFactory())(source)