[Dovecot] deliver saving mails with hard linking

http://dovecot.org/tmp/deliver-multiple.diff for Dovecot v1.1 implements -p <path> parameter for deliver, which reads the input mail from the specified path instead of stdin. With maildir and hardlink copying enabled, it also tries to hard link the file to destination instead of copying it.

So to get the same mail delivered to multiple recipients using hard links, you'd have to write a small wrapper script that stored the mail temporarily somewhere and then called deliver for each recipient using the -p parameter.

Any thoughts on if this should go to v1.1 like this? Some problems:

• If you're not using a single UID/GID you probably have to make the file world-readable.
• A wrapper script is kind of ugly, so it would be nice if deliver took a list of all recipients as input. But the deliver code is currently ugly enough that this would require larger changes.
• Am I forgetting something?..