Move identity-manager.cpp to identity subfolder.  Added initial private-key-storage.
diff --git a/ndn-cpp/security/identity/identity-manager.hpp b/ndn-cpp/security/identity/identity-manager.hpp
new file mode 100644
index 0000000..2557a03
--- /dev/null
+++ b/ndn-cpp/security/identity/identity-manager.hpp
@@ -0,0 +1,28 @@
+/**
+ * @author: Jeff Thompson
+ * See COPYING for copyright and distribution information.
+ */
+
+#ifndef NDN_IDENTITY_MANAGER_HPP
+#define	NDN_IDENTITY_MANAGER_HPP
+
+#include "../../data.hpp"
+
+namespace ndn {
+
+class IdentityManager {
+public:
+  /**
+   * 
+   * Note: the caller must make sure the timestamp in data is correct, for example with 
+   * data.getMetaInfo().setTimestampMilliseconds(time(NULL) * 1000.0).
+   * @param data The Data object to sign and update its signature.
+   * @param certificateName The Name identifying the certificate which identifies the signing key.
+   * @param wireFormat The WireFormat for calling encodeData, or WireFormat::getDefaultWireFormat() if omitted.
+   */
+  void signByCertificate(const Data& data, const Name& certificateName, WireFormat& wireFormat = *WireFormat::getDefaultWireFormat());
+};
+
+}
+
+#endif