message: Use ccache if available
diff: cmake_minimum_required(VERSION 3.1)
  project(Irrlicht LANGUAGES CXX C)
  +# Configure CCache if available
  +find_program(CCACHE_FOUND ccache)
  +if(CCACHE_FOUND)
  + set_property(GLOBAL PROPERTY RULE_LAUNCH_COMPILE ccache)
  + set_property(GLOBAL PROPERTY RULE_LAUNCH_LINK ccache)
  +endif(CCACHE_FOUND)
  +
  set(CMAKE_CXX_STANDARD 14)
  set(CMAKE_CXX_STANDARD_REQUIRED ON)
  set(CMAKE_CXX_EXTENSIONS OFF) #...without compiler extensions like gnu++11, but is it really needed?
  