[Dovecot] v1.1.20 released

http://dovecot.org/releases/1.1/dovecot-1.1.20.tar.gz http://dovecot.org/releases/1.1/dovecot-1.1.20.tar.gz.sig

Hopefully one of the last v1.1 releases.

* Upgraded to Unicode 5.2.0

- Maildir: Fixed crash when using a lot of keywords.
- file_set_size() was broken with OSes that didn't support
  posix_fallocate() (almost everyone except Linux), causing all kinds
  of index file errors.