highlight with mouse then shouldn't need kill-ring-save?

[Dan Jacobson]

Gentlemen, in (iceme) X Windows all we have to do is highlight some
text with the mouse, and then it is in the cut and paste buffer.

But with emacs, oh no, one must remember to hit ESC w which runs the
command kill-ring-save.

So emacs should go with the flow, as 9 times out of 10 we do this in X
so expect it for those times in emacs too... or make it an option...