Old numeric_cast<> completely replaced by new code (except that the old code is retained as a fallback mechanism for old broken compilers that can't deal with the new code)

[SVN r29761]

test/Jamfile

@@ -27,7 +27,6 @@ DEPENDS all : test ;
       : [ run implicit_cast.cpp ]
         [ compile-fail implicit_cast_fail.cpp ]
         [ run ../cast_test.cpp ]
-        [ run ../numeric_cast_test.cpp ]
         [ run ../lexical_cast_test.cpp ]
       ;
 }