transient-mark-mode: change default

[Reto Zimmermann]

I was wondering why the default for `transient-mark-mode' is nil.  I
guess most users (especially the novice users) would prefer the more
common behavior of `transient-mark-mode' but are not even aware of this
switch.  Also, the new command `comment-dwim' - which is a very powerful
commenting command for which I was always looking for - only works for
`transient-mark-mode' turned on.

How about changing the default for `transient-mark-mode' to non-nil?

Reto