Picture mode does not provide any hook on exit

[M Jared Finder]

I suggest adding a hook "picture-mode-exit-hook" which is run in 
picture-mode-exit.  Here's why:

Normally, activating a major mode calls kill-all-local-variables which runs 
change-major-mode-hook. 
Picture-mode does not do this, which makes sense because picture-mode is used 
as a temporary major
mode.  I use it all the time to draw pictures in my code comments.

I have written a minor mode that is incompatible with picture mode (both my 
mode and picture-mode
try to remap self-insert-command).  Normally, I would disable my minor mode by 
putting a null keymap
into minor-mode-overriding-map-alist, which would get killed when the major 
mode changed.  But since
picture-mode does not call kill-all-local-variables, this keymap does not get 
removed until I
expcitily re-enter the old major mode.

Adding an exit hook would allow me to remove the null keymap from 
minor-mode-overriding-map-alist,
without disturbing any other local variables.

  -- MJF

In GNU Emacs 22.0.50.1 (i486-pc-linux-gnu, GTK+ Version 2.8.13)  of 2006-03-23 
on pacem, modified by
Debian X server distributor `The X.Org Foundation', version 11.0.60900000 
configured using
`configure '--build' 'i486-linux-gnu' '--host' 'i486-linux-gnu' '--prefix=/usr'
'--sharedstatedir=/var/lib' '--libexecdir=/usr/lib' '--localstatedir=/var'
'--infodir=/usr/share/info' '--mandir=/usr/share/man' '--with-pop=yes'
'--enable-locallisppath=/etc/emacs-snapshot:/etc/emacs:/usr/local/share/emacs/22.0.50/site-lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/22.0.50/site-lisp:/usr/share/emacs/site-lisp:/usr/share/emacs/22.0.50/leim'
'--with-x=yes' '--with-x-toolkit=gtk' 'CFLAGS=-DDEBIAN -g -O2 -Wno-pointer-sign'
'build_alias=i486-linux-gnu' 'host_alias=i486-linux-gnu'' Important settings:   
value of $LC_ALL:
nil   value of $LC_COLLATE: nil   value of $LC_CTYPE: nil   value of 
$LC_MESSAGES: nil   value of
$LC_MONETARY: nil   value of $LC_NUMERIC: nil   value of $LC_TIME: nil   value 
of $LANG: nil  
locale-coding-system: nil   default-enable-multibyte-characters: t Major mode: 
Emacs-Lisp Minor
modes in effect:   eldoc-mode: t   global-balanced-mode: t   balanced-mode: t   
hrule-mode: t  
cua-mode: t   global-reveal-mode: t   reveal-mode: t   global-hi-lock-mode: t   
hi-lock-mode: t  
show-paren-mode: t   tooltip-mode: t   auto-compression-mode: t   
mouse-wheel-mode: t  
menu-bar-mode: t   file-name-shadow-mode: t   global-font-lock-mode: t   
font-lock-mode: t  
blink-cursor-mode: t   unify-8859-on-encoding-mode: t   utf-translate-cjk-mode: 
t  
column-number-mode: t   line-number-mode: t   transient-mark-mode: t Recent 
input: <down> <down>
<down> <down> <down> <down> <down> <down>  <down> <down> <down> <down> <down> 
<down> <down> <down> 
<down> <down> <down> <down> <down> <down> <down> <down>  <up> <up> <up> <up> 
<up> <up> <down>
<return> <up>  <return> ( d e f u n SPC b a l a n c e d - e n a b  l e - b a l 
a n c e d - m o d e
SPC ( ) <return> "  H o o k SPC f u n c t i o n <menu> r e p o r t SPC  e m 
<tab> <return> Recent
messages: Balanced mode disabled Undo! [4 times] Quit Undo! [3 times] Redo! 
Longlines mode disabled
Longlines mode enabled Auto-saving...done (No changes need to be saved) 
Auto-saving...done