* lisp/language/china-util.el (decode-hz-region): Pay
attention to "~~}" sequence at the end of Chinese character
range.
(hz-category-table): New variable.
(encode-hz-region): Convert non-encodable characters to
\u... and \U... Preserve ESC on ecoding. Put
`chinese-gb2312' `charset' text property in advance to force
iso-2022-encoding to select chinese-gb2312 designation.