src: Changing namespace ndn to namespace nfd

Also, this commit imports used classes from ::ndn namespace (from
NDN-CPP library) directly to ::nfd namespace.

refs: #1163

Change-Id: I9cc9d72e00af495b4ed0c84e6d418a7c9ba986cb
diff --git a/daemon/table/cs.cpp b/daemon/table/cs.cpp
index c0dc4e2..d85b2d0 100644
--- a/daemon/table/cs.cpp
+++ b/daemon/table/cs.cpp
@@ -8,7 +8,7 @@
 
 #include "cs.hpp"
 
-namespace ndn {
+namespace nfd {
 
 Cs::Cs()
 {
@@ -31,4 +31,4 @@
 }
 
 
-} //namespace ndn
+} //namespace nfd