[DOCS] add for 32.1.x

[TAKAHASHI Motonobu]

Hello,

I wrote a document about SWAT i18n feature, please check and I wish
this is added to 32.1.x.

=====
## enabling SWAT i18n message

SWAT can be configured to change its messeges for browser's language
setting (sent to SWAT in Accept-Language header in HTTP request).

Enabling this feature 

(1) you need to install proper msg files in source/po directory into
    $LIBDIR

(2) setting proper value for "display charset" parameter 

(3) Set your browser's language setting

The name of msg file is same as the language ID sent by the browser. For
example en means "English", ja means "Japanese". fr means "French, ...

If you do not like (some of) messeges or there is no *.msg file for
your language, you can create a new *.msg file simply to copy en.msg
to <your language ID>.msg and fill proper string to each "msgstr", for
example in it.msg (msg file for Italian)

msgid "Set Default"
msgstr "Imposta Default" 

and so on. If you find a mistake or create a new msg file, please send
to us and we will include this to the next release of Samba.

Note that if you enable this feature and "display charset" is not
matched to your browser's setting, the SWAT display may be corrupted.
In the feature version of Samba, SWAT will always display messege for
UTF-8 encoding and you will not need to set "display charset"
parameter.
=====

-----
TAKAHASHI, Motonobu (monyo)                    monyo at home.monyo.com
                                               http://www.monyo.com/