[project @ 2003-05-22 22:40:29 by cjwatson]

[project @ 2003-05-22 22:40:29 by cjwatson]
Improve display of MIME-encoded bugs. Now you get a link at the top of each
MIME part to the "download attachment" system we've had for a while; each
MIME part is decoded appropriately for display, so no more quoted-printable
rubbish; the actual text of an attachment is not displayed unless you use
the download link, so no more reams of base-64; and an extra "&mime=no"
parameter is provided in case there's anybody who liked the old display.

In addition, this fixes a few small bugs in the existing attachment
download system, such as those mentioned in #160389.