src: Expiration time change for LSA and Fib entry

Changed lifetime of LSA and FIB Entry to ndn::time::system_clock::TimePoint
type expiration timepoint. And refreshing event is scheduled at that timepoint

Refs: #1594

Change-Id: Ib31fe7ca79e79174eb3a5a4956ed5334da093b1b
diff --git a/src/route/fib-entry.cpp b/src/route/fib-entry.cpp
index ba2731f..f35bae7 100644
--- a/src/route/fib-entry.cpp
+++ b/src/route/fib-entry.cpp
@@ -37,6 +37,7 @@
 FibEntry::writeLog()
 {
   _LOG_DEBUG("Name Prefix: " << m_name);
+  _LOG_DEBUG("Time to Refresh: " << m_expirationTimePoint);
   _LOG_DEBUG("Seq No: " << m_seqNo);
   m_nexthopList.writeLog();
 }
@@ -45,7 +46,7 @@
 operator<<(ostream& os, FibEntry fe)
 {
   os << "Name Prefix: " << fe.getName() << endl;
-  os << "Time to Refresh: " << fe.getTimeToRefresh() << endl;
+  os << "Time to Refresh: " << fe.getExpirationTimePoint() << endl;
   os << fe.getNexthopList() << endl;
   return os;
 }