face, mgmt: add channel status dataset publisher

Expose channel maps in protocol factories

Change-Id: I057b1bba638bfc9372867318653d71ba7d0e9888
Refs: #1631, #1653
diff --git a/daemon/face/protocol-factory.hpp b/daemon/face/protocol-factory.hpp
index 8d61f9c..5a4a2f5 100644
--- a/daemon/face/protocol-factory.hpp
+++ b/daemon/face/protocol-factory.hpp
@@ -1,11 +1,12 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /**
- * Copyright (c) 2014  Regents of the University of California,
- *                     Arizona Board of Regents,
- *                     Colorado State University,
- *                     University Pierre & Marie Curie, Sorbonne University,
- *                     Washington University in St. Louis,
- *                     Beijing Institute of Technology
+ * Copyright (c) 2014,  Regents of the University of California,
+ *                      Arizona Board of Regents,
+ *                      Colorado State University,
+ *                      University Pierre & Marie Curie, Sorbonne University,
+ *                      Washington University in St. Louis,
+ *                      Beijing Institute of Technology,
+ *                      The University of Memphis
  *
  * This file is part of NFD (Named Data Networking Forwarding Daemon).
  * See AUTHORS.md for complete list of NFD authors and contributors.
@@ -20,7 +21,7 @@
  *
  * You should have received a copy of the GNU General Public License along with
  * NFD, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
- **/
+ */
 
 #ifndef NFD_DAEMON_FACE_PROTOCOL_FACTORY_HPP
 #define NFD_DAEMON_FACE_PROTOCOL_FACTORY_HPP
@@ -31,6 +32,7 @@
 namespace nfd {
 
 class Face;
+class Channel;
 
 /**
  * \brief Prototype for the callback called when face is created
@@ -68,6 +70,10 @@
   createFace(const FaceUri& uri,
              const FaceCreatedCallback& onCreated,
              const FaceConnectFailedCallback& onConnectFailed) = 0;
+
+  virtual std::list<shared_ptr<const Channel> >
+  getChannels() const = 0;
+
 };
 
 } // namespace nfd