Configure jakson mapper to serialize dates as timestamps

Author: sbrossie

src/main/java/org/killbill/billing/client/KillBillHttpClient.java

@@ -53,6 +53,7 @@
 
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.SerializationFeature;
 import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
 
 public class KillBillHttpClient implements Closeable {
@@ -173,6 +174,7 @@ public KillBillHttpClient(final String kbServerUrl,
 
         mapper = new ObjectMapper();
         mapper.registerModule(new JavaTimeModule());
+        mapper.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);
     }
 
     public KillBillHttpClient(final String kbServerUrl, final String username, final String password, final String apiKey, final String apiSecret) {