[Dovecot] [PATCH] example-config: fix to also distribute auth-dict.conf.ext in

Hi,

When trying to patch the dovecot 2.2.1 release with latest upstream patches I generated out of the repository, the patch fails to apply, because 'doc/example-config/conf.d/auth-dict.conf.ext' is not distributed within the release tarball.

Attached patch should fix the issue.

Cheers, Chris