Fix typos

Minor fixes to some logfile messages
Add DATE header to email messages

Add DATE header to avoid problems when script-generated email is
processed by, for example,  spam filters and email classifiers.
Use example.com instead of an actual domain name

Use 'example.com' (a domain name reserved for documentation and other
purposes, see RFC 2606 for details) in the default email configuration
section instead of an actual domain name in case this setting is not
altered by the user.