* todos.el: Rename numerous commands and defcustoms and adjust all

* todos.el: Rename numerous commands and defcustoms and adjust all
uses, change numerous key bindings, make some basic commands
noninteractive and use them to define the commands, unify
archiving commands.
(todos-directory): Rename from todos-files-directory.
(todos-print-buffer-function): Rename from todos-print-function.
(todos-number-prefix): Rename from todos-number-priorities.
(todos-top-priorities-overrides): Rename from todos-priorities-rules.
(todos-top-priorities): Rename from todos-show-priorities.
(todos-insertion-command-name, todos-insertion-key-bindings):
Use "todos-insert-item-".
(todos-key-bindings, todos-archive-mode-map)
(todos-categories-mode-map, todos-filtered-items-mode-map):
Adjust to renamed commands, make bindings more systematic,
reorder entries.
(todos-show-categories-table): Rename from todos-display-categories.
(todos-sort-categories-alphabetically-or-by-priority): Rename from
todos-display-categories-alphabetically-or-by-priority.
(todos-sort-categories-by-todo): Rename from
todos-display-categories-sorted-by-todo.
(todos-sort-categories-by-diary): Rename from
todos-display-categories-sorted-by-diary.
(todos-sort-categories-by-done): Rename from
todos-display-categories-sorted-by-done.
(todos-sort-categories-by-archived): Rename from
todos-display-categories-sorted-by-archived.
(todos-print-buffer): Rename function from todos-print.
(todos-print-buffer-to-file): Rename from todos-print-to-file.
(todos-go-to-source-item): Rename from todos-jump-to-item.
(todos-forward-item, todos-backward-item): Remove interactive form
and move most of doc string and prefix argument error checking to...
(todos-next-item, todos-previous-item): ...these new commands,
which use the preceding functions.
(todos-next-button): Rename from todos-forward-button.
(todos-previous-button): Rename from todos-backward-button.
(todos-toggle-prefix-numbers): Rename from
todos-hide-show-item-numbering.
(todos-toggle-view-done-items): Rename from todos-hide-show-done-items.
(todos-toggle-view-done-only): Rename from todos-show-done-only.
(todos-toggle-item-highlighting): Rename from todos-highlight-item.
(todos-toggle-item-header): Rename from todos-hide-show-date-time.
(todos-toggle-mark-item): Rename from todos-mark-unmark-item.
(todos-filter-top-priorities): Rename from todos-top-priorities.
(todos-filter-top-priorities-multifile): Rename from
todos-top-priorities-multifile.
(todos-filter-diary-items): Rename from todos-diary-items.
(todos-filter-diary-items-multifile): Rename from
todos-diary-items-multifile.
(todos-filter-regexp-items): Rename from todos-regexp-items.
(todos-filter-regexp-items-multifile): Rename from
todos-regexp-items-multifile.
(todos-insert-item-1): Remove interactive form, since
todos-insert-item is generated like other item insertion commands.
(todos-edit-file): Rename from todos-edit-multiline.
(todos-item-undone): Rename from todos-item-undo.
(todos-archive-done-item): Add raw prefix spec to interactive form
and use it to test for archiving all done items in category;
reorder tests in function body accordingly.
(todos-archive-category-done-items): Remove.