fix cronjob removed on purge (#269)

bin/mw

@@ -293,6 +293,7 @@ asktype() { while : ; do
 
 purge() { confirm "delete all account data" || exit
 	rm -rf "$mbsyncrc" "$accdir" "$HOME/.config/msmtp" "$cachedir"
+	crontab -l | sed '/mailsync/d' | crontab - >/dev/null
 	echo "All configs and account settings have been purged."
 	sed -ibu "/\# mw-autogenerated/d" "$muttrc" ; rm -f "$muttrc"bu
 }