Updated examples to support new packing/converting mechanism.

example/cpp03/class_intrusive.cpp

@@ -21,8 +21,7 @@
 #include <sstream>
 #include <cassert>
 
-// msgpack.hpp is also ok
-#include <msgpack_fwd.hpp>
+#include <msgpack.hpp>
 
 
 class my_class {
@@ -57,8 +56,6 @@ void print(std::string const& buf) {
     std::cout << std::dec << std::endl;
 }
 
-#include <msgpack.hpp>
-
 int main() {
     {   // pack, unpack
         my_class my("John Smith", 42);