bug#42210: bug#41890: 28.0.50; [PATCH]: Add bindings for project.el

[Juri Linkov]

> OK then, here's a question:
>
> Should project-other-place-commands include an entry for
> project-or-external-find-file?

I don't see why someone might want to use such commands as
project-or-external-find-file or project-or-external-find-regexp.
These commands operate on some obscure directories
(copied from the output of '(project-external-roots (project-current t))'):

"/usr/local/share/emacs/site-lisp/"
"/usr/share/emacs/site-lisp/autoconf/"
"/usr/share/emacs/site-lisp/gtk-doc-tools/"
...

I don't know why the user might want to find files or search in such
non-project directories as /usr/share/emacs/site-lisp/gtk-doc-tools/.