Update syntax for ndnpeek/ndnping in integration tests

refs #3694

Change-Id: I82ed673f5cf48da942dcfe59b36e76548bcb07bc
diff --git a/test_interest_aggregation/test_interest_aggregation.py b/test_interest_aggregation/test_interest_aggregation.py
index e93850b..8c85b1f 100644
--- a/test_interest_aggregation/test_interest_aggregation.py
+++ b/test_interest_aggregation/test_interest_aggregation.py
@@ -148,12 +148,12 @@
         #Fail if either is unanswered.
         peekOutputFile = os.path.abspath(self.logFolder + "test-peek-output-5.txt")
         self.startProcess("ndnpeek-5",
-            ["ndnpeek", "-l 6000", "ndn:/test-agg/C"],
+            ["ndnpeek", "--lifetime", "6000", "ndn:/test-agg/C"],
             "-> Starting Peek Client 5 (Prefix=ndn:/test-agg/C, InterestLifetime=6000ms)",
             outputFile=peekOutputFile)
         peekOutputFile = os.path.abspath(self.logFolder + "test-peek-output-6.txt")
         self.startProcess("ndnpeek-6",
-            ["ndnpeek", "-l 8000", "ndn:/test-agg/C"],
+            ["ndnpeek", "--lifetime", "8000", "ndn:/test-agg/C"],
             "-> Starting Peek Client 6 (Prefix=ndn:/test-agg/C, InterestLifetime=8000ms)",
             outputFile=peekOutputFile)
         self.waitForProcessCompletion("ndnpeek-5", 10)