implement resurrect cache for Message

helps a couple %. Might help more when making use of more caching
(html conversions in several ways) combined with multiple resurrect in
code because $m isn't around (perhaps this won't ever happen, though).
don't use personal example
--html-do: handle address 'comment' field correctly
--html-do: really handle address 'comment' field correctly
improve cook_subject
handle multipart/related
--html-to: show attachments
add array_any
handle multipart/mixed with text and ms-tnef parts
bug #2
fix --recurse with subdirs
bug #3
fix #3: no textual part found in the mail, toplevel content-type is 'multipart/mixed'