Examples: Header comments.

examples/sdl_opengl_example/imgui_impl_sdl.cpp

@@ -1,7 +1,7 @@
 // ImGui SDL2 binding with OpenGL
-// You can copy and use unmodified imgui_impl_* files in your project. 
+// You can copy and use unmodified imgui_impl_* files in your project. See main.cpp for an example of using this.
 // If you use this binding you'll need to call 4 functions: ImGui_ImplXXXX_Init(), ImGui_ImplXXXX_NewFrame(), ImGui::Render() and ImGui_ImplXXXX_Shutdown().
-// See main.cpp for an example of using this.
+// If you are new to ImGui, see examples/README.txt and documentation at the top of imgui.cpp.
 // https://github.com/ocornut/imgui
 
 #include <SDL.h>