Return JsonArray and JsonObject by value (closes #309)

examples/MsgPackParser/MsgPackParser.ino

@@ -55,7 +55,7 @@ void setup() {
   }
 
   // Get the root object in the document
-  JsonObject& root = doc.as<JsonObject>();
+  JsonObject root = doc.as<JsonObject>();
 
   // Fetch values.
   //
@@ -77,15 +77,4 @@ void loop() {
   // not used in this example
 }
 
-// See also
-// --------
-//
-// The website arduinojson.org contains the documentation for all the functions
-// used above. It also includes an FAQ that will help you solve any
-// deserialization problem.
-// Please check it out at: https://arduinojson.org/
-//
-// The book "Mastering ArduinoJson" contains a tutorial on deserialization.
-// It begins with a simple example, like the one above, and then adds more
-// features like deserializing directly from a file or an HTTP request.
-// Please check it out at: https://arduinojson.org/book/
+// Visit https://arduinojson.org/v6/example/msgpack-parser/ for more.