Reworking mail_spooler :
Fixed total count of emails to send not being fetched properly
Improved the loop processing emails
Fixed sent detection not working when SMTP queue was starting with 0 or a letter
When it detects a mail was already sent (missing send_time but the queue is filled), it fills the send_time field with same value than create_time. This is done for backward compatibility as this should not occur anymore
Conveniance function verb() to reduce code rewriting