* stops mutt from logging CRAM secrets in debug mode.

* stops mutt from logging CRAM secrets in debug mode.
* should fix mutt segfaulting when trying to open {}
* helps with the problem of mutt detecting new mail in the wrong
  folder. Now, IMAP commands from the SELECTED state should call
  imap_cmd_finish after they've executed commands. I've only put
  this is imap_buffy_check for now - in my opinion the command
  execution path is still not stable, and rewrites may obviate the
  need for this...

(From: Brendan Cully <brendan@kublai.com>)