lib-sieve: Improved (temporary) error handling from mail storage and io streams.

src/lib-sieve/cmd-redirect.c

src/lib-sieve/plugins/body/ext-body-common.c

src/lib-sieve/plugins/body/ext-body-common.h

src/lib-sieve/plugins/body/tst-body.c

src/lib-sieve/plugins/duplicate/tst-duplicate.c

src/lib-sieve/plugins/enotify/cmd-notify.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/notify/ext-notify-common.c

src/lib-sieve/plugins/notify/ext-notify-common.h

...ib-sieve/plugins/spamvirustest/ext-spamvirustest-common.c

...ib-sieve/plugins/spamvirustest/ext-spamvirustest-common.h

src/lib-sieve/plugins/spamvirustest/tst-spamvirustest.c

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

src/lib-sieve/sieve-actions.c

src/lib-sieve/sieve-interpreter.c

src/lib-sieve/sieve-interpreter.h

src/lib-sieve/sieve-message.c

src/lib-sieve/sieve-result.c