face, mgmt: add channel status dataset publisher

Expose channel maps in protocol factories

Change-Id: I057b1bba638bfc9372867318653d71ba7d0e9888
Refs: #1631, #1653
diff --git a/daemon/face/ethernet-factory.hpp b/daemon/face/ethernet-factory.hpp
index 5630141..4571a9e 100644
--- a/daemon/face/ethernet-factory.hpp
+++ b/daemon/face/ethernet-factory.hpp
@@ -5,7 +5,8 @@
  *                     Colorado State University,
  *                     University Pierre & Marie Curie, Sorbonne University,
  *                     Washington University in St. Louis,
- *                     Beijing Institute of Technology
+ *                     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.
@@ -82,6 +83,9 @@
   const MulticastFaceMap&
   getMulticastFaces() const;
 
+  virtual std::list<shared_ptr<const Channel> >
+  getChannels() const;
+
 private:
   void
   afterFaceFailed(const std::string& interfaceName,