core: move common.hpp to core/

Headers in core/ are now included as `#include "core/*.hpp"`.
This allows NFD to rely less on include paths when used as a submodule in
another codebase, such as ndnSIM and NFD-Android.

refs #3127

Change-Id: Ia38f3c97427e17ff7b5401281f1fe875b5d5313e
diff --git a/core/version.hpp.in b/core/version.hpp.in
new file mode 100644
index 0000000..189c9e6
--- /dev/null
+++ b/core/version.hpp.in
@@ -0,0 +1,74 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2014-2016,  Regents of the University of California,
+ *                           Arizona Board of Regents,
+ *                           Colorado State University,
+ *                           University Pierre & Marie Curie, Sorbonne University,
+ *                           Washington University in St. Louis,
+ *                           Beijing Institute of Technology,
+ *                           The University of Memphis.
+ *
+ * This file is part of NFD (Named Data Networking Forwarding Daemon).
+ * See AUTHORS.md for complete list of NFD authors and contributors.
+ *
+ * NFD is free software: you can redistribute it and/or modify it under the terms
+ * of the GNU General Public License as published by the Free Software Foundation,
+ * either version 3 of the License, or (at your option) any later version.
+ *
+ * NFD 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * NFD, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef NFD_CORE_VERSION_HPP
+#define NFD_CORE_VERSION_HPP
+
+namespace nfd {
+
+/** NFD version follows Semantic Versioning 2.0.0 specification
+ *  http://semver.org/
+ */
+
+// To change version number, modify VERSION variable in top-level wscript.
+
+/** \brief NFD version represented as an integer
+ *
+ *  MAJOR*1000000 + MINOR*1000 + PATCH
+ */
+#define NFD_VERSION @VERSION@
+
+/** \brief NFD version represented as a string
+ *
+ *  MAJOR.MINOR.PATCH
+ */
+#define NFD_VERSION_STRING "@VERSION_STRING@"
+
+/** \brief NFD version string, including git commit information, if NFD is build from
+ *         specific git commit
+ *
+ * NFD_VERSION_BUILD_STRING is obtained using the following command (`NFD-` prefix is
+ * afterwards removed):
+ *
+ *    `git describe --match 'NFD-*'`
+ *
+ * When NFD is built not from git, NFD_VERSION_BUILD_STRING equals NFD_VERSION_STRING
+ *
+ * MAJOR.MINOR.PATCH(-release-candidate-tag)(-(number-of-commits-since-tag)-COMMIT-HASH)
+ *
+ * Example, 0.1.0-rc1-1-g5c86570
+ */
+#define NFD_VERSION_BUILD_STRING "@VERSION_BUILD@"
+
+/// MAJOR version
+#define NFD_VERSION_MAJOR @VERSION_MAJOR@
+/// MINOR version
+#define NFD_VERSION_MINOR @VERSION_MINOR@
+/// PATCH version
+#define NFD_VERSION_PATCH @VERSION_PATCH@
+
+} // namespace nfd
+
+#endif // NFD_CORE_VERSION_HPP