Add ability to subscribe to 'both' and avoid a deadlock when switching. - 'both' means normal and digest versions simultaneously; information about this feature is not included in the default list texts, but a few power users find it helpful. - Only take out locks when actually performing a subscription, not before checking whether the address is already subscribed; we only really need it when we are actually changing the file, and there is a potential deadlock which could occur while waiting for unsubscription to complete as part of a switch if the lock is taken earlier. - Also moved code which sends unsubscription confirmations so that it only runs once, after unsubsciption has been completed, not every time the address is removed; this is only really important when 'both' is a realistic subscription option, but it could avoid other double-sends as well.

--- a/ChangeLog	Tue Jan 24 04:08:24 2012 +1100
+++ b/ChangeLog	Wed Jan 25 22:34:57 2012 +1100
@@ -1,3 +1,4 @@
+ o Add ability to subscribe to both (normal and digest).
  o Fix access logic so subonlypost doesn't override a send access rule.
  o Make +unsubscribe remove the requester from all versions of the list.
  o Make mlmmj-unsub default to removing the requester from all versions of the