Abort if close() fails on a filehandle opened for writing.
Support the "mime_require" access variable for the post command,
and the "noxform" mode for the rekey command.
Bugfix:  add existence tests to prevent autovivification of
  configuration variables.  Thanks to Roger Klorese.
(parse_attachment_rules)  Add support for the "format" and
 "require" actions.  The format action converts HTML or
 enriched text into plain text.  The require action sets the
 mime_require access variable.
(compile_pattern)  Escape unescaped solidi and dollar signs.
(_open_state)  Bugfix:  return an empty hashref if the _digests
file does not already exist.  Thanks to Roger Klorese.
(rekey)  Give a better indication of the keys that were changed,
verified, or repaired.
(aux_rekey)  Separate the xform and verification tasks.
(parse_entity)  Remove formatting from HTML parts and attempt to
process the commands.
(_post)  Abort if close() fails on a filehandle opened for writing.
    Add "X-Content-Reformatted" and "X-Content-Discarded" headers
    to messages that have been altered due to the attachment rules.
    Add headers to digests based upon the precedence, reply_to, and
    message_headers settings, for consistency with Mj1 digests.
    Thanks to Roger Klorese.
(_r_strip_body)  Remove the "concat" and "regcreset" ops from
    the Safe compartment for compatibility with perl 5.004.
    Instead of substituting for scalar variables, non-terminal
    dollar signs are automatically escaped.
    Thanks to Olivier Prenant.
    Add support for the "format" action, which converts HTML or
    enriched text into plain text.
    Thanks to Brian Heess.
(_format_text)  New routine.  Convert enriched text or
    HTML into plain text, or break long lines in a plain text
    body part.
(re_match)  Remove the concat and regcreset ops from the Safe
  compartment for compatibility with perl 5.004.
(enriched_to_hyper, plain_to_hyper)  New routines.  Convert
  enriched or plain text into HTML for conversion into formatted
  plain text by the HTML::FormatText module.
(getline)  Bugfix:  do not override a zero timeout multiplier,
  which is used for pipelining RCPT commands.
(address)  Revise code to deal properly with unusual responses.
(getresp)  Treat a 552 response as a failure.
Mention that new modules are required, and why.
(_post) Fix filehandle typo.
Add dot on suggested chown line.
Suggest separate chown and chgrp commands.
Describe the postblock flag better.
Contrast the tokeninfo-full and tokeninfo-remind commands.
When the digest command is used without any of the necessary modes,
list the supported digests and the modes.
Include the digest_mode error message.
Include an unsubscribe-farewell button.