Split BOOST_TEST_TRAIT_* into lightweight_test_trait.hpp.

test/is_same_test.cpp

@@ -8,9 +8,8 @@
 // http://www.boost.org/LICENSE_1_0.txt
 //
 
-#include <boost/iterator.hpp>
 #include <boost/core/is_same.hpp>
-#include <boost/core/lightweight_test.hpp>
+#include <boost/core/lightweight_test_trait.hpp>
 
 struct X
 {