Issue #77 Convert doxygen dummy headers to .dox files

Doxygen will treat them the same,
and it helps unclutter the C++ code.

src/blackcore/blackcore.dox

@@ -1,5 +1,10 @@
-#ifndef BLACKCORE_H
-#define BLACKCORE_H
+/* Copyright (C) 2013
+ * swift Project Community / Contributors
+ *
+ * This file is part of swift project. It is subject to the license terms in the LICENSE file found in the top-level
+ * directory of this distribution. No part of swift project, including this file, may be copied, modified, propagated,
+ * or distributed except according to the terms contained in the LICENSE file.
+ */
 
 //! \file
 
@@ -38,5 +43,3 @@
  * \defgroup dbus DBus related functions, classes, or definitions.
  * \ingroup blackcore
  */
-
-#endif // guard