security: delete deprecated signature-sha256.hpp

refs #2267

Change-Id: Ibd9cdb0fd2905da5615a89f6db01445752eabf2f
diff --git a/src/security/signature-sha256.hpp b/src/security/signature-sha256.hpp
deleted file mode 100644
index e04ba0f..0000000
--- a/src/security/signature-sha256.hpp
+++ /dev/null
@@ -1,30 +0,0 @@
-/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
-/**
- * Copyright (c) 2013-2014 Regents of the University of California.
- *
- * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
- *
- * ndn-cxx library is free software: you can redistribute it and/or modify it under the
- * terms of the GNU Lesser General Public License as published by the Free Software
- * Foundation, either version 3 of the License, or (at your option) any later version.
- *
- * ndn-cxx library is distributed in the hope that it will be useful, but WITHOUT ANY
- * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
- * PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more details.
- *
- * You should have received copies of the GNU General Public License and GNU Lesser
- * General Public License along with ndn-cxx, e.g., in COPYING.md file.  If not, see
- * <http://www.gnu.org/licenses/>.
- *
- * See AUTHORS.md for complete list of ndn-cxx authors and contributors.
- */
-
-#ifndef NDN_SECURITY_SIGNATURE_SHA256_HPP
-#define NDN_SECURITY_SIGNATURE_SHA256_HPP
-
-#include "digest-sha256.hpp"
-
-///@deprecated
-typedef DigestSha256 SignatureSha256;
-
-#endif //NDN_SECURITY_SIGNATURE_SHA256_HPP