Examples: added README file

examples/README.txt

@@ -0,0 +1,16 @@
+
+directx9_example/
+    DirectX9 example application (Windows).
+	
+directx11_example/
+    DirectX11 example (Windows).
+	
+opengl_example/
+    OpenGL exemple, using fixed pipeline (Windows/OSX/Linux etc., using glfw+glew)
+    This is simple and should work for all OpenGL enabled applications.
+
+opengl3_example/
+    OpenGL exemple, using programmable pipeline (Windows/OSX/Linux etc., using glfw+glew)
+    This uses more modern calls and custom shaders.
+    I don't think there is an advantage using this over the "simpler example, but it is provided for information.
+