[Dovecot] v1.2.12 released

http://dovecot.org/releases/1.2/dovecot-1.2.12.tar.gz http://dovecot.org/releases/1.2/dovecot-1.2.12.tar.gz.sig

Some of the most important fixes since v1.2.11:

- deliver: Don't crash when a message with Auto-submitted: header gets
  rejected.
- lib-storage: Fixed header searches to work correctly when there are
  multiple headers with same name.
- dict client: Disconnect from dict server after 1 second of idling.
- dict: If process crashed, it wasn't automatically restarted
- dict file: If dict file's group permissions equal world permissions,
  don't try to change its gid.
- maildir: Fixed a memory leak when copying with hardlinks.
- maildir: Expunging last messages may have assert-crashed if their
  filenames had just changed.