re-organising Emacs FTP

[Phillip Lord]

Currently, the Emacs FTP site has a single directory for windows binaries.

https://ftp.gnu.org/pub/gnu/emacs/windows/

It has binaries from Emacs 22 which are a decade old. Unfortunately,
these get listed first.

I would like to re-organise to add one directory per major release. So
at top-level we would have:

https://ftp.gnu.org/pub/gnu/emacs/windows/emacs-22
https://ftp.gnu.org/pub/gnu/emacs/windows/emacs-23
https://ftp.gnu.org/pub/gnu/emacs/windows/emacs-24
https://ftp.gnu.org/pub/gnu/emacs/windows/emacs-25
https://ftp.gnu.org/pub/gnu/emacs/windows/emacs-26

With a symlink from

https://ftp.gnu.org/pub/gnu/emacs/windows/latest

The reason for this is that, with Emacs-26 there will be four binaries
with every release (with-deps, no-deps in 32 and 64 bit), as well as the
dependencies independently (perhaps these are not necessary now) and,
finally, source for all the deps. Plus all the sig files.

For Emacs-27, the situation gets worse as I there is the new windows
installer bringing the number of binaries up to 6.

Obviously, this change would break things for anyone who has scripted
the installation. But it would clean up the experience for anyone who
has not.

I am not proposing on changing the source directory, as that's Nicolas'
bag really.

https://ftp.gnu.org/pub/gnu/emacs/

Thoughts?

Phil