lib-sieve: Switched to new Dovecot SMTP API.

src/lib-sieve/cmd-redirect.c

src/lib-sieve/plugins/enotify/mailto/ntfy-mailto.c

src/lib-sieve/plugins/enotify/sieve-ext-enotify.h

src/lib-sieve/plugins/notify/cmd-notify.c

src/lib-sieve/plugins/vacation/cmd-vacation.c

src/lib-sieve/sieve-actions.c

src/lib-sieve/sieve-smtp.c

src/lib-sieve/sieve-smtp.h

src/lib-sieve/sieve-types.h

src/plugins/lda-sieve/lda-sieve-plugin.c

src/sieve-tools/sieve-test.c

src/testsuite/testsuite-smtp.c

src/testsuite/testsuite-smtp.h