add namespace for requester

Change-Id: I3de037dffd702edff9f87a87e8e684161db3d329
diff --git a/src/requester-state.cpp b/src/requester-state.cpp
index 4cb448b..0c4755d 100644
--- a/src/requester-state.cpp
+++ b/src/requester-state.cpp
@@ -22,6 +22,7 @@
 
 namespace ndn {
 namespace ndncert {
+namespace requester {
 
 RequesterState::RequesterState(security::KeyChain& keyChain, const CaProfile& caItem, RequestType requestType)
   : m_caItem(caItem)
@@ -30,5 +31,6 @@
 {
 }
 
+} // namespace requester
 } // namespace ndncert
 } // namespace ndn
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