(quail-install-map): New optional arg

(quail-install-map): New optional arg
NAME.
(quail-get-translation): If DEF is a symbol but not a function,
ignore it.
(quail-start-translation): Put a key sequence undefined in the
translation keymap in unread-command-events, not generated-events.
Return parameterized event (compose-last-chars N) if the input
characters should be composed.
(quail-map-definition): If DEF is t, treat it as nil.
(quail-delete-last-char): Delete the quail region.
(quail-show-translations): Don't show list of translations if the
quail package is deterministic.
(quail-completion-max-depth): New variable.
(quail-completion-1): Pay attention to the above variable.  Fix
for the case that a translation is a function.
(quail-map-from-table, quail-map-from-table-1,
quail-map-from-table-2): New functions.
(quail-lookup-map-and-concat): New function