BGE docs: resolution & fullscreen changes don't work in the embedded player

The documentation for bge.render.{setWindowSize,setFullScreen,getFullScreen}
did not mention that those functions are no-ops when using the Blender-
embedded player.

doc/python_api/rst/bge.render.rst

@@ -108,6 +108,9 @@ Functions
 
    Set the width and height of the window (in pixels). This also works for fullscreen applications.
 
+   .. NOTE::
+       Only works in the standalone player, not the Blender-embedded player.
+
    :type width: integer
    :type height: integer
 
@@ -115,12 +118,19 @@ Functions
 
    Set whether or not the window should be fullscreen.
 
+   .. NOTE::
+       Only works in the standalone player, not the Blender-embedded player.
+
    :type enable: bool
 
 .. function:: getFullScreen()
 
    Returns whether or not the window is fullscreen.
 
+   .. NOTE::
+       Only works in the standalone player, not the Blender-embedded player;
+       there it always returns False.
+
    :rtype: bool
 
 .. function:: getDisplayDimensions()