Merge changes made in Gnus trunk.

Merge changes made in Gnus trunk.

gnus-art.el (gnus-article-next-page): Change last-line-displayed behaviour.
 (article-lapsed-string): Refactor out and allow specifying how many segments you want.
 (gnus-article-setup-buffer): Start updating the lapsed header directly.
 (gnus-article-update-lapsed-header): New variable.
shr.el (shr-put-color): Don't do the box padding in tables, since they're already padded.
gnus-util.el (float-time): If float-time is bound, always use it on all Emacsen.  It's unclear why the subrp check was there.
 (time-date): Require to make some autoload issues on XEmacs go away.
gnus-draft.el (gnus-draft-clear-marks): New function to be run as an exit hook to nix out all data on readedness on group exit.
gnus-sum.el (gnus-auto-select-subject): Doc typo.