This conversion now includes a check that may fail. Pigeonhole currently only
uses this functionality to obtain an SMTP version of the postmaster address.
This code is now consolidated in the sieve_get_postmaster_smtp() function, which
provides postmaster address as an SMTP address.

Now using struct smtp_address rather than sieve_address.
In some cases, struct message_address may prove to be more suitable, but this is the best fit for now.
Adjusted to the renamed fields in struct mail_deliver_context.

Used the following script:

C_FILES=`git ls-files *.c`
H_FILES=`git ls-files *.h`
for F in "$C_FILES $H_FILES"; do
        echo "$F"
  perl -p -i -e 's/safe_memset\(&\(?([^,]*)\)?,\s*0,\s*sizeof\(\g1\)\)/i_zero_safe(&$1)/g' $F
  perl -p -i -e 's/safe_memset\(([^,]*),\s*0,\s*sizeof\(\*\g1\)\)/i_zero_safe($1)/g' $F
  perl -p -i -e 's/memset\(&\(?([^,]*)\)?,\s*0,\s*sizeof\(\g1\)\)/i_zero(&$1)/g' $F
  perl -p -i -e 's/memset\(([^,]*),\s*0,\s*sizeof\(\*\g1\)\)/i_zero($1)/g' $F
done

lib-sieve: util: Removed Pigeonhole's own version of t_str_trim(), since it is now available in Dovecot.

This is used mainly when no other means of obtaining the user's email is available, such as when there is no envelope (in IMAP).
Before, the postmaster address or the null "<>" address was used as a fallback for sending messages.
The redirect and enotify commands can be explicitly configured to use what is configured with sieve_user_email.

Used wrong type in sizeof().