[Nmh-workers] Release engineering updates

[Ken Hornstein]

So, I had the following items on my 1.6 release wishes:

- Always run mhbuild on outgoing drafts.
- Have mhbuild handle RFC-2047 encoding
- Allow content-transfer-encoding in an mhbuild directive.
- Default to 8bit C-T-E (when required)
- Support RFC 2231 MIME extended parameter encoding and decoding
- Support character set conversion for mhshow(1) using iconv
- Adapt meillo's changes to mhshow(1) so each MIME part doesn't use their
  own pager.
- Not display items marked as "attachment" by default in mhshow(1).
- Maybe make mhshow(1) the default instead of show(1).
- Find a home for MH-V (not necessarily a release blocker).

The first 4 are done!  I was going to work on RFC 2231 support next.  The
next three I think are easy.  I'm not sure yet about making mhshow the
default.  As for MH-V (Steve Rader's curses front-end to nmh), well, I have
the latest release thanks to his co-workers.  But I think Steve was using
an old version of nmh, because when I tried to run it there were some errors,
so it needs some love.  Is anyone interested in taking it on?

Anything else people want to cram into 1.6?

--Ken