* ispell.el (ispell-set-spellchecker-params): New function to make sure

* ispell.el (ispell-set-spellchecker-params): New function to make sure
right params and dictionary alists are used after spellchecker changes.
(ispell-aspell-dictionary-alist, ispell-last-program-name)
(ispell-initialize-spellchecker-hook): New variables and hook.
(ispell-find-aspell-dictionaries): Use ispell-aspell-dictionary-alist.
(ispell-maybe-find-aspell-dictionaries): Remove.
Calls replaced by (ispell-set-spellchecker-params) calls.
(ispell-have-aspell-dictionaries): Remove.
* flyspell.el: Replace ispell-maybe-find-aspell-dictionaries by
ispell-set-spellchecker-params.