lsdb: emit signals when modified

RoutingTable and NamePrefixTable consume the signal
and behave accordingly.

refs: #4127

Change-Id: I6540f30f0222f804b01dc7d9640831c84e5264cc
diff --git a/tests/test-statistics.cpp b/tests/test-statistics.cpp
index 016d51e..0000fb0 100644
--- a/tests/test-statistics.cpp
+++ b/tests/test-statistics.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2014-2020,  The University of Memphis,
+ * Copyright (c) 2014-2021,  The University of Memphis,
  *                           Regents of the University of California,
  *                           Arizona Board of Regents.
  *
@@ -47,8 +47,6 @@
 
     addIdentity(conf.getRouterPrefix());
 
-    nlsr.initialize();
-
     this->advanceClocks(ndn::time::milliseconds(1), 10);
     face.sentInterests.clear();
   }