[Exim] Use $address_data in local_scan()

Hi!

It would be useful to be able to have access to the $address_data
strings for each recipient address from within local_scan() function,
for example by adding "uschar *data" member to recipient_item structure.

This would allow to lookup users' preferences during ACL address
verification, save it in $address_data, and then use it in local_scan()
- for example to be able to fine-tune the recipient list based on
whether the particular user wants the messages filtered by the MTA, or
not.

That way the lookup would only be done once, by the router.

I know there are $acl_xx variables, but why copy the data back and
forth in the ACLs?

What do you think?

regards,

Marcin
--
Marcin Owsiany
porridge@???