Add CJK codecs support as discussed on python-dev. (SF #873597)

Several style fixes are suggested by Martin v. Loewis and
Marc-Andre Lemburg. Thanks!

Lib/test/test_codecmaps_cn.py

@@ -0,0 +1,34 @@
+#!/usr/bin/env python
+#
+# test_codecmaps_cn.py
+#   Codec mapping tests for PRC encodings
+#
+# $CJKCodecs: test_codecmaps_cn.py,v 1.2 2004/01/17 12:47:19 perky Exp $
+
+from test import test_support
+from test import test_multibytecodec_support
+import unittest
+
+class TestGB2312Map(test_multibytecodec_support.TestBase_Mapping,
+                   unittest.TestCase):
+    encoding = 'gb2312'
+    mapfilename = 'EUC-CN.TXT'
+    mapfileurl = 'http://people.freebsd.org/~perky/i18n/EUC-CN.TXT'
+
+class TestGBKMap(test_multibytecodec_support.TestBase_Mapping,
+                   unittest.TestCase):
+    encoding = 'gbk'
+    mapfilename = 'CP936.TXT'
+    mapfileurl = 'http://www.unicode.org/Public/MAPPINGS/VENDORS/' \
+                 'MICSFT/WINDOWS/CP936.TXT'
+
+def test_main():
+    suite = unittest.TestSuite()
+    suite.addTest(unittest.makeSuite(TestGB2312Map))
+    suite.addTest(unittest.makeSuite(TestGBKMap))
+    test_support.run_suite(suite)
+
+test_multibytecodec_support.register_skip_expected(TestGB2312Map, TestGBKMap)
+if __name__ == "__main__":
+    test_main()
+