bug#62750: 29.0.50; Commands 'package-update' and 'package-update-all' should be called '*-upgrade'

[Eli Zaretskii <eliz@gnu.org>]

> Date: Mon, 24 Apr 2023 02:06:45 +0300
> From: Dmitry Gutov <dmitry@gutov.dev>
> Cc: adam@alphapapa.net, philipk@posteo.net, larsi@gnus.org,
>  62750@debbugs.gnu.org
> 
> Here's a couple of other existing functions:
> 
>    package--update-selected-packages
>    package--update-downloads-in-progress
> 
> Neither of these relate to upgrading packages. Although the former could 
> be easy to mistake for that now.
> 
> In all older functions, the term "update" (in comments and variable 
> names) refers to updating the value of some variable, not packages.
> 
> By analogy, 'M-x package-update-all' might be easy enough to mistake for 
> updating the list of packages available for installation, for example.
> 
> Here's a patch that does the rename. Also including package-vc-update* 
> that Philip mentioned.

Any objections to these renames, anyone?

Does anyone think we need to leave behind aliases for the old names?

Me, I have only one potential issue: since "update" just means "delete
the installed version, then install another version", it could be
easily made to downgrade, not just to upgrade.  So if we ever would
like to allow downgrading, the new names will get in the way.  But if
this is not an issue we should be bothered about, it's fine by me.

Thanks.