(appt-check): For minutes in between appt-display-interval times,
do check, but don't display anything except an updated mode line.
Count against appt-display-interval based on minutes since
first display of this appointment, not based on time of day.
If appt-display-mode-line, force mode line redisplay
whenever appt-mode-string has changed.
(appt-add, appt-delete): Add autoload cookies.
(appt-check): Catch errors from calling `diary'.
(appt-max-time): Renamed from max-time.
(appt-now-displayed, appt-display-count): New variables.
(appt-timer): Don't create one if we already have one.
(global-mode-string): Add appt-mode-string to it.
(appt-check): Avoid using display-time-string to fetch current time.
To display in mode line, use appt-mode-string.
(appt-delete): Don't set tmp-appt-msg-list.
(appt-delete-window): Avoid error if WINDOW is nil.
(appt-delete-window): Do nothing if the window
is the only one in its frame.
appt-disp-window-function and appt-delete-window-function.
(appt-disp-window-function): New variable.
(appt-delete-window-function): New variable.
(appt-delete-window): New function.
(appt-disp-window): Don't delete the appt window here;
instead, call appt-delete-window-function.
Fixed bug that messed up the screen when appt-check ran
when mouse is in the minibuffer.
Call select-frame only if window-system.
