mouse-autoselect-window custom nit

[Marshall, Simon]

Thanks for implementing delayed mouse-autoselect-window.

Just a doc nit - the custom value menu has "Off (nil)" as an entry.  
I don't think the lisp value corresponding to entry should be shown.

Simon.

*** cus-start.el.~1.96.~        Mon Sep 11 10:38:42 2006
--- cus-start.el        Mon Sep 11 11:31:48 2006
***************
*** 363,369 ****
             (overline-margin display integer "22.1")
               (mouse-autoselect-window
              display (choice
!                      (const :tag "Off (nil)" :value nil)
                       (const :tag "Immediate" :value t)
                       (number :tag "Delay by secs" :value 0.5)) "22.1")
             ;; xfaces.c
--- 363,369 ----
             (overline-margin display integer "22.1")
               (mouse-autoselect-window
              display (choice
!                      (const :tag "Off" :value nil)
                       (const :tag "Immediate" :value t)
                       (number :tag "Delay by secs" :value 0.5)) "22.1")
             ;; xfaces.c