Added support to handle unconfigured sendmail, i.e. the program catches sendmail warnings. Now handles nodes that are temporarily down. Prints out a warning to the screen - doesn't report this as an error on the SMS, syslog or email. Avoids unneccesary warnings. Added date and time in the warnings strings.
Exception is the syslog entry, which already has a time stamp.
The format is a short string to get below the 160 bytes available for the SMS message. Removed the persistent popup warning window method imposed by v0.0.3. Now uses a standard window. Remember to close the window using the menus. General stability increased.