(ido-setup-hook): New hook.

(ido-setup-hook): New hook.
(ido-define-mode-map-hook): Remove hook; use ido-setup-hook instead.
(ido-input-stack): New var.
(ido-define-mode-map): Bind M-b to ido-push-dir. Move old
ido-next-work-file binding to M-O.
Bind M-f to ido-wide-find-file-or-pop-dir.
(ido-define-mode-map): Don't run ido-define-mode-map-hook.
(ido-read-internal): Run ido-setup-hook.
Catch quit in read-file-name and read-string to cancel edit.
Handle new push, pop, and pop-all exit codes (for M-b/M-f).
Automatically pop-all when completing a directory name (RET).
(ido-file-internal): Add with-no-warnings around ffap and dired code.
(ido-exit-minibuffer): Use exit-minibuffer instead of throw.
(ido-wide-find-file, ido-wide-find-dir): Catch quit to cancel find.
(ido-push-dir, ido-pop-dir, ido-wide-find-file-or-pop-dir): New
functions for M-b/M-f to move among the directory components.
(ido-make-merged-file-list): Catch quit to cancel merge.
(ido-make-dir-list): Delete "." when ido-input-stack is non-empty.
(ido-completion-help): No warnings for ido-completion-buffer-full.