/// <summary>
 /// Sends a promotional email to an audience list. NOTE: Requires a subscription to the
 /// mailer API.
 /// </summary>
 /// <param name="item">Mailer Item to send</param>
 /// <param name="listName">Audience List to send to</param>
 /// <param name="promotionName">Name of the promotion</param>
 /// <returns>Transaction ID</returns>
 public ApiResult SendPromotion(MailItem item, string listName, string promotionName)
 {
     return PostToMadMimi("/to_list", item.BuildRequest(promotionName, listName), true);
 }
 /// <summary>
 /// Sends a transactional email. NOTE: Requires a subscription to the mailer API.
 /// </summary>
 /// <param name="item">Mailer Item to send</param>
 /// <returns>Transaction ID</returns>
 public ApiResult SendEmail(MailItem item, string promoName)
 {
     return PostToMadMimi("", item.BuildRequest(promoName), true);
 }