Member Flag: digest

Subscribers with this flag set receive the digested form of the mailing
list, rather than the regular form.

The "regular" form of the list is the traditional mailing list format.
Each time a subscriber sends something to the list, everyone on the list
receiving the "regular" list format receives a copy of the submission
exactly as it was sent to listmanager.

The "digest" form of the list is a compressed format, with most headers
of each submission stripped away, and submissions grouped together
and only sent out when certain thresholds are exceeded.  The thresholds
are maintained by the list owners, and include the size of the
digest, the number of items in the digest, and the frequency at which
they are sent.  Many people find this format far more convenient.
