build BUGFIX fix location for the generated config.h files
config.h is included from the source codes using relative paths, so
when the file is generated by cmake, store it with source codes.
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8dae6ec..0394e4f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -134,7 +134,7 @@
add_subdirectory(tests)
endif()
-configure_file(src/config.h.in src/config.h)
+configure_file("${PROJECT_SOURCE_DIR}/src/config.h.in" "${PROJECT_SOURCE_DIR}/src/config.h" ESCAPE_QUOTES @ONLY)
configure_file(nc_client.h.in nc_client.h)
configure_file(nc_server.h.in nc_server.h)