email file attachments

[Paul Rubin]

It would be really useful if Mail mode had a way to put MIME file
attachments into the outgoing message.  I guess Rmail should also
recognize attachments if it doesn't yet; I haven't used Rmail in a
long time so that doesn't matter to me as much.  But C-x m is the
simplest way I know to send mail, so I use it all the time, and
being able to send attachments would make it even better.