Made ARROWLESS_KBD a preference.

Replace the ARROWLESS_KBD #define with the ViKeyMenus preference.

When ViKeyMenus is TRUE, users can type h/j/k/l to scroll around menus.

Since ARROWLESS_KBD was previously undefined by default, ViKeyMenus is
FALSE by default.

src/WindowMaker.h

@@ -324,6 +324,7 @@ typedef struct WPreferences {
     char opaque_move_resize_keyboard; /* update window position during move,resize with keyboard */
     char wrap_menus;		       /* wrap menus at edge of screen */
     char scrollable_menus;	       /* let them be scrolled */
+    char vi_key_menus;		       /* use h/j/k/l to select */
     char align_menus;		       /* align menu with their parents */
     char use_saveunders;	       /* turn on SaveUnders for menus, icons etc. */
     char no_window_over_dock;