Improve how to redefine macros in 2011/toledo

The new variables in the Makefile, with defaults, are:

    FIRE= XK_BackSpace:XK_Tab
    FORWARD= XK_Up:XK_w
    BACKWARD= XK_Down:XK_s
    LEFT= XK_Left:XK_a
    RIGHT= XK_Right:XK_d
    WIDTH= 512
    HEIGHT= 288

An example of how to set some is in the README.md file.

This commit means I can remove an item from the things-todo.md file
which I have now done. Next I can return to 2018.

thanks-for-help.md

@@ -3315,6 +3315,9 @@ lets one reconfigure the controls and also the size of the game and another
 version that should work in Windows, based on the author's remarks and support
 file, `layer.c`.
 
+The Makefile was also modified by Cody to make it simpler to redefine the
+controls, width and height.
+
 
 ## <a name="2011_vik"></a>[2011/vik](/2011/vik/vik.c) ([README.md](/2011/vik/README.md]))