refs #1131 #1136 Change-Id: I3e97cb17bf85082b6499a310120409379f8eaa65
Also, this commit imports used classes from ::ndn namespace (from NDN-CPP library) directly to ::nfd namespace. refs: #1163 Change-Id: I9cc9d72e00af495b4ed0c84e6d418a7c9ba986cb
refs #1128 Change-Id: I8943ad07d93422dc456fd051b2e4c0d5f38bc227