Adding transient to Emacs core

[Jonas Bernoulli]

Hello,

A while go [1] we discussed adding Transient to Emacs core, not just GNU
Elpa.  The consensus appeared to be that it should be added to Emacs, so
that other core packages could use it, which I agree with.  I would like
to do that now.

I would prefer to continue maintaining Transient in its current
repository [2] and only import releases into the Emacs repository.
At first I would like to only import "transient.el", later also
"transient.texi".  (At this point friendlier documentation is the
area that needs the most work.)

So what do you think; should be proceed with this?

     Cheers,
     Jonas

[1]: id:e329f68a-21d2-6c1a-5528-44c4e8513091@posteo.net
     https://lists.gnu.org/archive/html/emacs-devel/2021-02/msg01384.html
[2]: [git clone] https://github.com/magit/transient.git