core: drop std::function and ndn::Exclude from common.hpp, add ndn::optional

Change-Id: Ie3983d8b6f9929430efd8ada8d942e3f95755cd4
diff --git a/tools/nfdc/fib-module.cpp b/tools/nfdc/fib-module.cpp
index 3da24ee..ef2841e 100644
--- a/tools/nfdc/fib-module.cpp
+++ b/tools/nfdc/fib-module.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
-/**
- * Copyright (c) 2014-2016,  Regents of the University of California,
+/*
+ * Copyright (c) 2014-2018,  Regents of the University of California,
  *                           Arizona Board of Regents,
  *                           Colorado State University,
  *                           University Pierre & Marie Curie, Sorbonne University,
@@ -32,7 +32,7 @@
 
 void
 FibModule::fetchStatus(Controller& controller,
-                       const function<void()>& onSuccess,
+                       const std::function<void()>& onSuccess,
                        const Controller::DatasetFailCallback& onFailure,
                        const CommandOptions& options)
 {