[Dovecot] v2.0.rc6 released

http://dovecot.org/releases/2.0/rc/dovecot-2.0.rc6.tar.gz http://dovecot.org/releases/2.0/rc/dovecot-2.0.rc6.tar.gz.sig

I expect this to be the last release candidate. Unless release critical bugs are reported, I'll update the version number to v2.0.0 on Monday morning without any other changes.

Since rc5 there have been mainly some small fixes and some error message improvements. The only (somewhat) important fixes are:

- dict quota didn't always decrease quota when messages were expunged
- Shared INBOX wasn't always listed with FS layout