management: ensure Element::Error inherits from tlv::Error

Add static asserts to ensure ndn::nfd::*::Error are subclasses of tlv::Error.

Add WireEncodable and WireDecodable concept checks to
ndn::nfd::* classes that represent TLV abstraction.

Move definition of ChannelStatus, FibEntry, ForwarderStatus,
StrategyChoice methods into .cpp.

Move declaration of FaceScope, FacePersistency, LinkType
into encoding/nfd-constants.hpp.

Eliminate duplicate RibFlags declaration.

refs #1983

Change-Id: I207bae479aa6da54a581a7cca5b2a13743827ff0
diff --git a/src/encoding/nfd-constants.cpp b/src/encoding/nfd-constants.cpp
new file mode 100644
index 0000000..8723bd7
--- /dev/null
+++ b/src/encoding/nfd-constants.cpp
@@ -0,0 +1,83 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2013-2014 Regents of the University of California.
+ *
+ * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
+ *
+ * ndn-cxx library is free software: you can redistribute it and/or modify it under the
+ * terms of the GNU Lesser General Public License as published by the Free Software
+ * Foundation, either version 3 of the License, or (at your option) any later version.
+ *
+ * ndn-cxx library is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+ * PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more details.
+ *
+ * You should have received copies of the GNU General Public License and GNU Lesser
+ * General Public License along with ndn-cxx, e.g., in COPYING.md file.  If not, see
+ * <http://www.gnu.org/licenses/>.
+ *
+ * See AUTHORS.md for complete list of ndn-cxx authors and contributors.
+ */
+
+#include "nfd-constants.hpp"
+#include <iostream>
+
+namespace ndn {
+namespace nfd {
+
+std::ostream&
+operator<<(std::ostream& os, FaceScope faceScope)
+{
+  switch (faceScope) {
+  case FACE_SCOPE_NON_LOCAL:
+    os << "non-local";
+    break;
+  case FACE_SCOPE_LOCAL:
+    os << "local";
+    break;
+  default:
+    os << "unknown";
+    break;
+  }
+  return os;
+}
+
+std::ostream&
+operator<<(std::ostream& os, FacePersistency facePersistency)
+{
+  switch (facePersistency) {
+  case FACE_PERSISTENCY_PERSISTENT:
+    os << "persistent";
+    break;
+  case FACE_PERSISTENCY_ON_DEMAND:
+    os << "on-demand";
+    break;
+  case FACE_PERSISTENCY_PERMANENT:
+    os << "permanent";
+    break;
+  default:
+    os << "unknown";
+    break;
+  }
+  return os;
+}
+
+std::ostream&
+operator<<(std::ostream& os, LinkType linkType)
+{
+  switch (linkType) {
+  case LINK_TYPE_POINT_TO_POINT:
+    os << "point-to-point";
+    break;
+  case LINK_TYPE_MULTI_ACCESS:
+    os << "multi-access";
+    break;
+  default:
+    os << "unknown";
+    break;
+  }
+  return os;
+}
+
+} // namespace nfd
+} // namespace ndn