[Dovecot] Apple patch 9

[Timo Sirainen]

  - Logging doesn't use the auth_request_log_*() calls like rest of  
the Dovecot-auth. Now things like service name (imap, pop3, ..) or  
remote IP address aren't logged.

  - The debug logging probably could be enabled with auth_debug=yes  
instead of a separate debug option. Although it seems like it's more  
meant for developers with the __LINE__ and __FUNCTION__ strings and  
things like refcounts which aren't useful for admins.

  - The debug logging seems to be written mostly for developers. Are  
they still even useful at that level (e.g. refcounts  More admin- 
oriented debug logging (with auth_debug=yes) would also have been  
helpful.

  - The hardcoded maildir: and quota_rule stuff won't get in like  
that. :) They'll have to be configurable somehow. Actually couldn't  
the whole configuration have been just like with ldap db? (Or actually  
the ldap config is a bit annoying, I was planning on making the user/ 
pass_attrs be configured a bit differently.)

  - Passing in_od_info->mem_pool all around just seems to make the  
code more confusing, since I doubt it's ever going to be anything else  
than system_pool?

  - CRAM-MD5 and APOP request/response handler stealing is pretty  
evil, especially with the duplicated structs. I'm sure there's a  
better way, although probably requires larger changes.

  - There are a lot of imap/pop3 references. How would e.g.  
managesieve work?

  - I'd change several if + i_error() checks to just i_assert()s.