Add README syntax highlighting

Author: ulikoehler

README.md

@@ -20,35 +20,37 @@ To use the library in your program, include msgpack.hpp header and link "msgpack
 
 
 ## Example
-
-    #include <msgpack.hpp>
-    #include <vector>
+```CPP
+#include <msgpack.hpp>
+#include <vector>
 
-    int main(void) {
-        // This is target object.
-        std::vector<std::string> target;
-        target.push_back("Hello,");
-        target.push_back("World!");
+int main(void) {
+    // This is target object.
+    std::vector<std::string> target;
+    target.push_back("Hello,");
+    target.push_back("World!");
 
-        // Serialize it.
-        msgpack::sbuffer sbuf;  // simple buffer
-        msgpack::pack(&sbuf, target);
+    // Serialize it.
+    msgpack::sbuffer sbuf;  // simple buffer
+    msgpack::pack(&sbuf, target);
 
-        // Deserialize the serialized data.
-        msgpack::unpacked msg;    // includes memory pool and deserialized object
-        msgpack::unpack(&msg, sbuf.data(), sbuf.size());
-        msgpack::object obj = msg.get();
+    // Deserialize the serialized data.
+    msgpack::unpacked msg;    // includes memory pool and deserialized object
+    msgpack::unpack(&msg, sbuf.data(), sbuf.size());
+    msgpack::object obj = msg.get();
 
-        // Print the deserialized object to stdout.
-        std::cout << obj << std::endl;    // ["Hello," "World!"]
+    // Print the deserialized object to stdout.
+    std::cout << obj << std::endl;    // ["Hello," "World!"]
 
-        // Convert the deserialized object to staticaly typed object.
-        std::vector<std::string> result;
-        obj.convert(&result);
+    // Convert the deserialized object to staticaly typed object.
+    std::vector<std::string> result;
+    obj.convert(&result);
 
-        // If the type is mismatched, it throws msgpack::type_error.
-        obj.as<int>();  // type is mismatched, msgpack::type_error is thrown
-    }
+    // If the type is mismatched, it throws msgpack::type_error.
+    obj.as<int>();  // type is mismatched, msgpack::type_error is thrown
+}
+```
+
 
 API documents and other example codes are available at the [wiki.](http://redmine.msgpack.org/projects/msgpack/wiki)