bug#21998: Run 'make change-history' on release branch

[Eli Zaretskii <eliz@gnu.org>]

> From: Glenn Morris <rgm@gnu.org>
> Date: Fri, 04 Mar 2016 11:46:49 -0500
> 
> At this point, I give up, since it seems fairly clear that maintaining
> an accurate ChangeLog just isn't of interest. Even the bare minimum
> legally relevant mistakes (missing "tiny change") don't seem to be being
> corrected. Probably just deleting it from the repo would be more honest.
> This will simplify things, eg the "correct log entries" step for making
> a release can be dropped, and the AUTHORS file can become less accurate.
> A rough non-versioned ChangeLog can still be generated for tarballs, if
> anyone cares. Or, a version of the above, stop keeping a versioned copy
> on any branch but master.

I think if we care at all about having ChangeLog in the releases, we
should simply reinstate the file and maintain it in the repository.  I
think this one-year experiment clearly demonstrates that creating
ChangeLog from VCS logs simply doesn't work well enough.  Look how
much energy we invested in making that happen, and we are still
nowhere as close to the solution as we'd like to be.

OTOH, if one has git-merge-changelog installed, the conflicts in
merging ChangeLog are very rare, and their resolution is simple.

Other projects, like GDB, still maintain ChangeLog files, and don't
seem to have any problems.

So I'd say let's go back to maintaining a ChangeLog (a single file in
the top-level directory), if we want a ChangeLog in the releases.  And
if we don't do that, let's decide there will be no ChangeLog files in
the release tarballs at all, and stop worrying about these issues.
What we have been trying to do -- both eat the cake and have it --
simply doesn't work.

John?