=head2 cleanbody

This module checks the body of an incoming article and cleans it up,
attempting to enforce standard ISO 8859-1 text.  If it's encoded in
quoted-printable, that encoding is undone.  Microsoft Word SmartQuotes are
converted into their ASCII equivalents, any Ctrl-Ms are removed, and the
module checks to make sure that the message contains no invalid characters
(outside of the standard ISO 8859-1 range) and that no lines are longer
than 79 characters.

The messages returned by the checks in the event of failure are:

=over 4

=item Invalid characters in body

The body contains characters outside the range [\s!-~\xa0-\xff].

=item Line over 79 characters

One or more lines in the body are over 79 characters long.

=back

This module takes no arguments or configuration directives.  If the
original message was in quoted-printable, it will change the
Content-Transfer-Encoding header to be "8bit".  It recognizes
quoted-printable from the MIME encoding headers.