Help avoid non-message false positives
Make mbox splitting script
Fix automatic tarball naming

Exotic characters are now translated into hyphens, allowing for
friendly filenames.  For example, a search for this:

^To: idm@hyperreal\.

Will now create a tarball named this:

-To--idm-hyperreal-.tar

Instead of giving this error message:

tar: Cannot connect to hyperreal..tar: resolve failed