message: If CMAKE_BUILD_TYPE isn't set then set it to RelWithDebInfo
diff: cmake_minimum_required(VERSION 3.0.2)
  project(NWNX-Unified)
  +if(NOT CMAKE_BUILD_TYPE)
  + set(CMAKE_BUILD_TYPE RelWithDebInfo)
  +endif()
  +
  if (NOT CMAKE_BUILD_TYPE STREQUAL "RelWithDebInfo")
  message( FATAL_ERROR "NWNX:EE can only be built with the CMAKE_BUILD_TYPE=RelWithDebInfo configuration." )
  endif()
  