SDL2 example builds.

src2/CMakeLists.txt

@@ -15,7 +15,7 @@ target_include_directories(${DUSK_LIBRARY_TARGET_NAME}
 
 # Main Binary Source
 target_sources(${DUSK_BINARY_TARGET_NAME}
-  PUBLIC
+  PRIVATE
     main.cpp
     sdl_starter.cpp
     sdl_assets_loader.cpp