The extended buffy for mh had incorrect placement of the loop
brackets.  The counters weren't being incremented in the loop.

Fix extended buffy for maildir to count a maildir message as new if it
doesn't have the info delimeter.

Remove shortcircuits added to the basic buffy stating there is new
mail when (msg_unread > 0).  This is not necessarily true, depending
on $mail_check_recent.

Note: the extended buffy still needs more fixes, which will be done
when it is refactored into its own option.