src: Remove unnecessary uses of boost::cref in make_shared and replace boost::cref/boost::ref with just cref/ref

In some cases, due to argument-dependent lookup, it is necessary to use
ndn::ref, instead of just ref.

Change-Id: I682180a007609535855f77511b49622154ad4f11
Refs: #1591
diff --git a/daemon/fw/available-strategies.cpp b/daemon/fw/available-strategies.cpp
index fce0fc5..c6f7d42 100644
--- a/daemon/fw/available-strategies.cpp
+++ b/daemon/fw/available-strategies.cpp
@@ -33,7 +33,7 @@
 shared_ptr<Strategy>
 makeDefaultStrategy(Forwarder& forwarder)
 {
-  return make_shared<BestRouteStrategy>(boost::ref(forwarder));
+  return make_shared<BestRouteStrategy>(ref(forwarder));
 }
 
 template<typename S>
@@ -42,7 +42,7 @@
 {
   StrategyChoice& strategyChoice = forwarder.getStrategyChoice();
   if (!strategyChoice.hasStrategy(S::STRATEGY_NAME)) {
-    strategyChoice.install(make_shared<S>(boost::ref(forwarder)));
+    strategyChoice.install(make_shared<S>(ref(forwarder)));
   }
 }