[Dovecot] v1.2.3 released

http://dovecot.org/releases/1.2/dovecot-1.2.3.tar.gz http://dovecot.org/releases/1.2/dovecot-1.2.3.tar.gz.sig

A few days later than I wanted, but here it is.

* Mailbox names with control characters can't be created anymore.
  Existing mailboxes can still be accessed though.

+ Allow namespace prefix to be opened as mailbox, if a mailbox
  already exists in the root dir.
- Maildir: dovecot-uidlist was being recreated every time a mailbox
  was accessed, even if nothing changed.
- listescape plugin was somewhat broken
- Compiling fixes for non-Linux/BSDs
- imap: tb-extra-mailbox-sep workaround was broken.
- ldap: Fixed hang when >128 requests were sent at once.
- fts_squat: Fixed crashing when searching virtual mailbox.
- imap: Fixed THREAD .. INTHREAD crashing.