def send!
      raise "job #{job.backup_id} has no email option" unless job.options[:email]
      # define local variables for closure over Mail.new
      from_address  = settings['email_from']
      to_address    = job.options[:email]
      subject_text  = "Backup of RDS #{job.rds_id} (job ID #{job.backup_id})"
      body_text     = body
      mail = Mail.new do
        from    from_address
        to      to_address
        subject subject_text
        body    "#{body_text}\n"
      end
      mail.deliver!
    end
def send!
      raise "job #{job.backup_id} has no email option" unless job.options[:email]
      # define local variables for closure over Mail.new
      from_address  = settings['email_from']
      to_address    = job.options[:email]
      subject_text  = "Backup of RDS #{job.rds_id} (job ID #{job.backup_id})"
      body_text     = body
      mail = Mail.new do
        from    from_address
        to      to_address
        subject subject_text
        body    "#{body_text}\n"
      end
      mail.deliver!
    end
constructor - requires an RDSBackup::Job
 Attempts to send email through local ESMTP port 25.
 Raises an Exception on failure.