Added the default private key and finish implementing defaultSign.
diff --git a/tests/test-encode-decode-data.cpp b/tests/test-encode-decode-data.cpp
index 2a7ebd8..6c18437 100644
--- a/tests/test-encode-decode-data.cpp
+++ b/tests/test-encode-decode-data.cpp
@@ -147,6 +147,8 @@
     Data freshData(Name("/ndn/abc"));
     const unsigned char freshContent[] = "SUCCESS!";
     freshData.setContent(freshContent, sizeof(freshContent) - 1);
+    freshData.getSignedInfo().setTimestampMilliseconds(256);
+
     
     KeyChain::defaultSign(freshData);
     cout << endl << "Freshly signed data:" << endl;