pginstaller - pginst: add the chinese (PRC) zh-CN.

Log Message:
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add the chinese (PRC) zh-CN.
this work is Ian Li.

Modified Files:
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pginst/lang:
languages.projinc (r1.4 -> r1.5)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pginstaller/pginst/lang/languages.projinc.diff?r1=1.4&r2=1.5)

Added Files:
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pginst/lang:
zh_cn.xml (r1.1)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pginstaller/pginst/lang/zh_cn.xml?rev=1.1&content-type=text/x-cvsweb-markup)
zh_cn_welcome.rtf (r1.1)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pginstaller/pginst/lang/zh_cn_welcome.rtf?rev=1.1&content-type=text/x-cvsweb-markup)