Merge pull request #515 from qxo/fix4MessagePackFactory

MessagePackFactory should add getFormatName for naming the factory

Author: komamitsu

msgpack-jackson/src/main/java/org/msgpack/jackson/dataformat/MessagePackFactory.java

@@ -172,4 +172,10 @@ ExtensionTypeCustomDeserializers getExtTypeCustomDesers()
     {
         return extTypeCustomDesers;
     }
+
+    @Override
+    public String getFormatName()
+    {
+        return "msgpack";
+    }
 }