* mime-ui-en.texi, mime-ui-ja.texi: Sync up with .sgml files.

* mime-ui-en.texi, mime-ui-ja.texi: Sync up with .sgml files.
* mime-ui-en.sgml, mime-ui-ja.sgml: Modify a description for simplified
`pgp-function-alist'.

* semi-def.el (pgp-function-alist): Simplify. Use `mime-mc-encrypt-region',
`mime-mc-traditional-sign-region', `mime-mc-sign-region' and
`mime-mc-fetch-key' for it.

* mime-mc.el (mime-mc-insert-public-key, mime-mc-snarf-keys, mime-mc-decrypt,
mime-mc-verify): Add doc strings.
(mime-mc-encrypt-region, mime-mc-traditional-sign-region, mime-mc-sign-region,
mime-mc-fetch-key): New functions.
(TopLevel): Add autoloads "mc-gpg", "mc-pgp5" and "mc-pgp" for the functions
`mc-gpg-fetch-key', `mc-gpg-sign-region', `mc-pgp50-fetch-key',
`mc-pgp50-sign-region', `mc-pgp-fetch-key' and `mc-pgp-sign-region'.

* mime-pgp.el (mime-pgp-fetch-key): Kill useless buffers after fetching.
(mime-pgp-show-fetched-key-for-pgp50, mime-pgp-show-fetched-key): Show fetched
key in the window of `mime-echo-buffer-name' if it is alive, otherwise use
`display-buffer'; minimize the window height; return buffer object to be
killed.