Update config.guess and config.sub and enable ./autogen.sh to do so

[binki]

IMO, config.guess and config.sub and ./configure and other things I’m forgetting about should be put in .gitignore and only included in dist tarballs. But since atheme seems to want to include them, this is what I had to do to get ./configure to run cleanly on my system. See #39.

At least with this PR ./autogen.sh is fixed to be smart enough to update config.sub and config.guess (which may be patched to the user’s environment, for example), so if these don’t work for others they can at least fix it themselves now instead of having to manually look for them.

[grawity]

I have no experience with autotools, but I wonder if it wouldn't be better to fix the buildsystem so that autoreconf -f -i would work like in other projects...

[binki]

@grawity idk why it is this way, but libmowgli2 uses this “buildsys.mk” thing because it’s not libtool+automake. libmowgli2’s use of AC_CANONICAL_TARGET and AC_CANONICAL_HOST rely on config.guess and config.sub which is provided by Automake. Enabling autoreconf -fi to work for libmowgli2 like it does for other autotools projects would mean switching to Automake and dropping buildsys.mk. If libmowgli2 really wants to do this, I would be willing to submit a PR, but it might take me a bit of time. Or another way of fixing #39 would just be to grab updated config.guess and config.sub files from the most recent Automake relase manually and commit them to the repo (that’d be a continuation of the status quo).

As I stated before, I personally don’t like how ./configure (a generated file), config.sub, config.guess, install-sh, etc., and even buildsys.mk itself (buildsys is its own project and including it in the VCS is like committing the source tree of a dependency, e.g., openssl to your own VCS). I do recognize that bundling this stuff doing this makes it easier for people to start contributing, especially if they’re only modifying a few lines of C. But it’s kind of noise in the VCS history…

As an aside, I actually haven’t yet managed to compile libmowgli2 under MSYS2 yet. And, at the very moment, my MSYS2 dev environment is tied to a broken keyboard xD. But if I do make any headway I will try to at least post any changes I made as I suppose others might like to see it working under MSYS2.

So, let me know which option you want:

1. This patch (stay with buildsys.mk and use an ugly hack to get ./autogen.sh to be able to update config.guess and config.sub).
2. A PR that just does a one-off update of config.guess and config.sub from a contemporary Automake release (continuation of the status quo).
3. Switching to Automake+libtool/getting autoreconf -fi to work (I’d be surprised if this is the consensus :-p).

[maxteufel]

I think switching to automake+libtool would be a good idea (same applies to atheme itself) since the current build system looks quite messy to me. But please let others comment on this as well.

Cc: @ilbelkyr @siniStar7boy