fixed a couple typo's, and a metrowerks porting issue

[SVN r8450]

stl_concept_check.cpp

@@ -63,7 +63,7 @@ main()
   function_requires< BackInsertionSequenceConcept<List> >();
 
 #ifndef BOOST_NO_SLIST
-  typedef std::slist<int> SList;
+  typedef BOOST_STD_EXTENSION_NAMESPACE::slist<int> SList;
   function_requires< FrontInsertionSequenceConcept<SList> >();
 #endif