(quail-guidance-buf): Make it buffer

(quail-guidance-buf): Make it buffer
local.
(quail-guidance-win): New variable.  Make it buffer local.
(quail-current-translations): Doc-string modified.
(quail-current-data): Make it buffer local.
(quail-define-package): Update input-method-alist.
(quail-defrule): Doc-string modified.
(quail-defrule-internal): Document it.
(quail-get-translation): Change the format of DEF part.
(quail-lookup-key): Make the second argument LEN optional.  Reset
quail-current-translations to nil.
(quail-map-definition): New funtion.
(quail-get-current-str): New function.
(quail-guidance-translations-starting-column): New variable.
(quail-update-current-translations): New function.
(quail-translate-key): Adjusted for the change of DEF format.
Call quail-update-current-translations
(quail-next-translation): Call quail-update-current-translations.
(quail-prev-translation): Likewise.
(quail-next-translation-block): Likewise.
(quail-prev-translation-block): Likewise.
(quail-select-translation): Deleted.
(quail-make-guidance-frame): New function.
(quail-show-guidance-buf): Handle the case that minibuffer is in a
separate frame.
(quail-hide-guidance-buf): Likewise.
(quail-show-translations): Call
quail-update-current-translations.  Check width of a frame to be
used.
(quail-completion): Do not supply LEN argument to
quail-lookup-key.
(quail-help): Use with-output-to-temp-buffer.
(quail-translation-help): Likewise.
(quail-conversion-help): Likewise.
(quail-update-leim-list-file): Save buffer without making a backup
file.