new emacs framework

[Thomas Klausner <wiz%netbsd.org@localhost>]

Hi!

TL;DR: new emacs framework in tree, some PKGNAMEs changed, some
packages will be removed

With a lot of help from Showta Ishizaki (thank you very much!) I've
just committed improvements to the emacs module framework
(editors/emacs/modules.mk).

It now supports the features we expect from a module framework:

- allow specifying supported versions

- allow specifying unsupported versions

- reduce conflicts between versions (this is not as important as
  e.g. for Python, because the base emacs* and xemacs* packages still
  conflict with each other)

- tag the PKGNAME with the version it was built for; so e.g. "magit"
  is now called "emacs30-magit" etc. depending on the version it was
  built for

- build all supported versions of a module in bulk builds

Different to the other frameworks:

- we have emacs* and emacs*nox, the reduced version without X support;
  since they use the same byte compiler and provide the same
  functions, there is only one emacs30-foo package that supports both
  emacs30 and emacs30-nox11 by default. This also means you only need
  to specify "emacs30" in EMACS_VERSIONS_ACCEPTED; if a package really
  only supports one of the two "flavors", you can forbid the other
  version in EMACS_VERSIONS_INCOMPATIBLE - we don't have any such
  packages in the tree right now.

I've done repeated bulk builds and marked all packages with the
(x)emacs versions that they were packaging successfully for. I have
_not_ tested all of them, and it might be possible to fix some of
them.

This currently leaves the following packages without _any_ (x)emacs
version that builds them:

chat/emacs-jabber
devel/ecb
devel/semantic
mail/vm
misc/elscreen
misc/lookup
wip/cedet
wip/elscreen-current
wip/slime
wip/undo-tree

I plan on removing these packages from the tree in a week, unless
someone speaks up for them. (In the meantime, they will just fail to
build and should not cause bulk build scan failures - at least they
don't for me.)

Enjoy!
 Thomas