LimitMail sends out mail, but keeps track of the recipients
and limits the number of mails they're getting.
Typical uses of LimitMail are applications sending out
automatic notification emails. If a system goes berserk and keeps sending
out emails, we don't want to fill up the user's mailbox. Instead, the
first message should be sent and subsequent mail requests should be
discarded until a selectable time period is over.
the base of the NDBM file which LimitMail uses internally
as a persistent store for who got mail and when.
It defaults to /tmp/limitmail, resulting in two NDBM files
/tmp/limitmail.dir and /tmp/limitmail.pag.
send_interval specifies the time interval in which Limitmail will
discard messages instead of sending them after a message has been submitted.
It defaults to 3600 * 24 (one day).
mailer_options is a reference to an array, containing parameters which
will be used by Limitmail internally to construct a Mail::Mailer
object. Check the Mail::Mailer documentation for details. It defaults to