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/mgmt/fib-manager.cpp b/daemon/mgmt/fib-manager.cpp
index 0936f5c..98c4578 100644
--- a/daemon/mgmt/fib-manager.cpp
+++ b/daemon/mgmt/fib-manager.cpp
@@ -108,7 +108,7 @@
   if (unsignedVerbProcessor != m_unsignedVerbDispatch.end())
     {
       NFD_LOG_DEBUG("command result: processing verb: " << verb);
-      (unsignedVerbProcessor->second)(this, boost::cref(request));
+      (unsignedVerbProcessor->second)(this, request);
     }
   else if (COMMAND_UNSIGNED_NCOMPS <= commandNComps &&
            commandNComps < COMMAND_SIGNED_NCOMPS)