Add Nack handling to CS freshness test and localhop test

Bring implementation of localhop test in line with design

refs #3692

Change-Id: I40c49b68b03aa1996e5546465daaccc18e29853e
diff --git a/test_localhop/test_localhop.py b/test_localhop/test_localhop.py
index 28c3ced..a2789c8 100644
--- a/test_localhop/test_localhop.py
+++ b/test_localhop/test_localhop.py
@@ -27,10 +27,9 @@
         print "Test script return value:", ret
         errormsg = {
             1 : "Invalid command line arguments",
-            2 : "Fail to add nexthop of ndn:/localhop",
-            3 : "Interest with name ndn:/localhop/test-localhop/A/1 was received on host C",
-            4 : "ndn:/localhop/test-localhop/A/1 is answered.",
-            5 : "ndn:/localhop/test-localhop/B/1 is not correctly answered.",
+            2 : "Failed to add nexthop of ndn:/localhop",
+            3 : "Interest with name ndn:/localhop/test-localhop/1 was received on host C",
+            4 : "Interest ndn:/localhop/test-localhop/1 answered with a Data.",
         }
         if (ret != 0):
             self.fail(errormsg[ret])