* calendar/todos.el (todos-window-configuration): Comment out.

* calendar/todos.el (todos-window-configuration): Comment out.
(todos-display-categories): Comment out use of
todos-window-configuration; use switch-to-buffer instead of
pop-to-buffer.
(todos-jump-to-category-noninteractively): Comment out use of
todos-window-configuration.
(todos-edit-item): Don't allow editing of date/time item header.
(todos-insert-item, todos-insert-item-here): Insert date/time
header in front of new item string.
(todos-mode): Tweak wrap-prefix.