Scratch buffer annoyance

[Chong Yidong]

This recent change leads to annoying behavior:

2007-07-02  Richard Stallman  <address@hidden>

        * startup.el (command-line): Set buffer-offer-save in *scratch*
        and enable auto-save in it.

After this was checked in, I noticed Emacs kept asking me if I wanted
to save the *scratch* buffer upon each exit.  That was annoying, but
tolerable, so I just answered "no".  A while later, I happened to do
an `ls' in my home directory, and found it cluttered with 10-20
auto-save files:

#*scratch*#10823QZW#
#*scratch*#220140RY#
#*scratch*#72802aU#
...

At the very least, we should (i) offer an option to adopt the Emacs 22
behavior for the *scratch* buffer, i.e. with buffer-offer-save and
auto-save disabled, and (ii) delete the auto-save file if the user
answers "no" when asked if *scratch* should be saved.