reading message left when image url on a tty

[Kevin Ryde <user42_kevin@xxxxxxxxxxxx>]

With current cvs on the console or "emacs -nw", if a http target url is
type image/png then the "reading ..." message remains after reading has
in fact finished.  (Doesn't happen for file://, only http://.)

Going blank would be ok.  Something to say image undisplayable would be
cute, maybe with mime type and/or emacs image type to hint why.

I struck this under "dbab" which blocks advertising and bad sites by
faking dns to go localhost and there serving dummy 1x1 image/gif
-- not great for text mode, but as long as emacs-w3m doesn't say
"reading" when it's not then that's ok.