autoconf / m4 update

[mywave82]

• Split up acinclude.m4 into separate m4 files makes it easier to maintain
• update the .m4 files
• Add regen.sh for persons who are not experient in automake/autoconf

This is one of the details pointed out in #23 by @dmitrysmagin

[Malvineous]

Is regen.sh better than running autoreconf?

[mywave82]

Is regen.sh better than running autoreconf?

I followed a guide that probably was outdated, but which commands autoreconf implies probably depends on the version of it, and considering we have bugreports about gcc 4.x toolchain issues in adplug I guess it didn't hurt.

[mywave82]

Also autoreconf fails if you are changing m4 stuff and already have existing Makefile. Then you either need to purge manually or run the commands manually as implied in ./regen.sh

(testing out replacing the outdated getopt files with using libgnu tools, so experiences these edge cases while in process)

[Malvineous]

Interesting, fair enough. I'm no expert but I assumed autoreconf was supposed to avoid the need for a shell script, but if it doesn't work, then I have no problem with the shell script.

The main AdPlug readme has for a long time suggested to run autoreconf --install - I presume that doesn't fare any better in those situations you mention?

[mywave82]

autoreconf --install should work for most use-cases, but if there any failures or autotools stop working while hacking on it, the steps inside ./regen.sh should get you back on-track.

I can update readme to include that later (I'm about to log off)

[mywave82]

Just merged info from regen.sh into README instead