mgmt: moved signing into AppFace, code streamlining, and bug fixes

tests/management: improved callback validation

Fixed bad shared_ptr NULL checks
Fixed bad iterator decrement in InternalFace.sendInterest
Removed semi-useless constants in FibManager
Clarified ControlResponse text messages

Change-Id: Ic327a0b6b57827e401c7c3115d0ee92bae996a34
refs: #1138
diff --git a/daemon/mgmt/app-face.hpp b/daemon/mgmt/app-face.hpp
index af58cdf..b6e2ab5 100644
--- a/daemon/mgmt/app-face.hpp
+++ b/daemon/mgmt/app-face.hpp
@@ -9,9 +9,11 @@
 
 #include "common.hpp"
 
+#include <ndn-cpp-dev/security/key-chain.hpp>
+
 namespace nfd {
 
-typedef ndn::func_lib::function<void(const Name&, const Interest&)> OnInterest;
+typedef function<void(const Name&, const Interest&)> OnInterest;
 
 class AppFace
 {
@@ -21,10 +23,16 @@
                     OnInterest onInterest) = 0;
 
   virtual void
+  sign(Data& data);
+
+  virtual void
   put(const Data& data) = 0;
 
   virtual
   ~AppFace() { }
+
+protected:
+  ndn::KeyChain m_keyChain;
 };
 
 } // namespace nfd