(gnus-namazu-index-directory): Abolished.

(gnus-namazu-index-directory): Abolished.
(gnus-namazu-index-directories): New option.
(gnus-namazu-coding-system): Changed the default value for Windows
and OS/2.
(gnus-namazu/setup): Follow the abolition of
`gnus-namazu-index-directory'.
(gnus-namazu/normalize-results): New inline function.
(gnus-namazu/call-namazu): Set `file-name-coding-system' and
`pathname-coding-system' to handle querys which include multibyte
characters.  Not reset locale environments.  Refer
`gnus-namazu-locale' and `gnus-namazu-index-directories'.
(gnus-namazu/search): Call `gnus-namazu/normalize-results'.
Modify a regular expression.
(gnus-namazu/get-target-groups): Modify a regular expression.
(gnus-namazu/get-current-query): Ditto.
(gnus-namazu/truncate-article-list): Ditto.