bug#43323: Rename cua-mode to something better?

[Sebastian Urban]

> In my opinion, these menu entry name & manual changes are unnecessary. 

So, after reading "Gather a list of confusions beginner tend to have"
thread in emacs-devel, especially (part of) message by Tomas:

   Witness: CUA. Most people think these days "CUA" means: "Copy" [1]
   is bound to "C-c", "Cut" [2] is bound to "C-x" and "Paste" [3] to
   "C-v".

   But according to IBM's "Common User Architecture" (aka "CUA" [4]),
   it's "C-Insert", "S-Del", and "S-Ins" respectively. But Apple's [5]
   infantilised version ("C-x" is the "scissors", etc.) somehow snuck
   in.

I guess I was too optimistic about CUA "standard", and proposal to
rename cua-mode to something else, as well as other related changes,
are actually good.


S. U.