bug#43884: Give explanation choice when asking about reverting buffers

[積丹尼 Dan Jacobson]

Revert buffer from file /cf/updates/TABZ? (yes or no) ?

Sounds serious. How about adding a "?" option that would tell the user
what that means:

Revert buffer from file /cf/updates/TABZ? (yes or no or ?) ?

So if he hits "?" a *Help* buffer would appear telling him the serious
consequences of each of the two choices.

After looking at
http://www.gnu.org/software/emacs/manual/html_node/emacs/Reverting.html

we see the message should say
"Yes: Throw away the changes you made in the buffer and replace them with the
saved version of the file from disk."