Add GB18030 tests.

	修改：     .gitignore
	删除：     tests/Makefile.in
	删除：     tests/check-ebcdic
	删除：     tests/check-tag
	修改：     tests/tests.cmake
	重命名：   tests/uniq-u.cpp -> tests/uniq-u.c

Author: ChenPi11

.gitignore

@@ -21,6 +21,7 @@ CTestCostData.txt
 *.inst
 Testing
 *.log
+*.dSYM
 
 # Test suite runable
 tests/cmp
@@ -56,6 +57,8 @@ build-aux/
 
 # Temp tests files.
 tests/data/UTF-8.TXT
+tests/data/GB18030-2005.TXT
+tests/data/GB18030-2022.TXT
 
 # Dist directory and temps
 cppp-reiconv-v*