Annual dues reminders automated

Sending reminder emails to diplomates to pay their annual dues is now automated.

• A first reminder is sent 1st March. It also warns you that the reduced early bird rate ends at the end of March.
• A second reminder is sent 1st of April.
• A last reminder is sent 1st of May.
• The 1st of June the treasurer will receive notice of those who have not yet paid their dues and the treasurer will follow up manually.

Let's hope it works as I meant it to be...