detail: move common.hpp to 'detail'
common.hpp and config.hpp are implementation details that should be
installed to target system.
common-pch.hpp is moved to 'impl'.
This commit also adds README.md to 'detail' and 'impl'
directories to explain their semantics.
refs #4782
Change-Id: I4f3e607338b3bdccbaddaed735f6326adcc2fda0
diff --git a/tests/unit/ndebug.t.cpp b/tests/unit/ndebug.t.cpp
index 7f1bb5a..39dcd8f 100644
--- a/tests/unit/ndebug.t.cpp
+++ b/tests/unit/ndebug.t.cpp
@@ -19,7 +19,7 @@
* See AUTHORS.md for complete list of ndn-cxx authors and contributors.
*/
-#include "ndn-cxx/common.hpp"
+#include "ndn-cxx/detail/common.hpp"
#include "tests/boost-test.hpp"