Do not compile ChronoSync support by default

ChronoSync dependency is now made optional
and is kept for testing purposes only.

Also change sig-type to ecdsa-sha256 in nlsr.conf
as ndn-cxx now has strict checking for it.

refs: #5147

Change-Id: I95c9fb844681ebf2c4e7bbb03cc7796a0795de83
diff --git a/tests/test-common.hpp b/tests/test-common.hpp
index 495f0ba..0f18dd7 100644
--- a/tests/test-common.hpp
+++ b/tests/test-common.hpp
@@ -177,7 +177,7 @@
 
 public:
   DummyConfFileProcessor(ConfParameter& conf,
-                         int32_t protocol = SYNC_PROTOCOL_PSYNC,
+                         SyncProtocol protocol = SYNC_PROTOCOL_PSYNC,
                          int32_t hyperbolicState = HYPERBOLIC_STATE_OFF,
                          ndn::Name networkName = "/ndn", ndn::Name siteName = "/site",
                          ndn::Name routerName = "/%C1.Router/this-router")