Append all messages from an mbox file to the selected folder with the
import-mbox command.
User confirmation is required when the folder already contains messages.
A failed append will be retried a few times. If a backend timeout
occurs, the entire import is stopped to prevent a hang.
Signed-off-by: Koni Marti <koni.marti@gmail.com>
Acked-by: Robin Jarry <robin@jarry.cc>
