and fix performance issues with Scale2x on GCW0 port
plus numerous other fixes.
This means that Triple/double buffering works properly with audio non
blocking support now.
I will probably regret doing huge commits like this one but
i'm too lazy to make smaller commits out of it so i'll make a
huge changelog instead.
I tried to make it more modular and this is the result of it.
In the Makefiles, you can easily choose the Sound API of your liking
as well as the fine-tuned SDL port you want to use.
Sound output : I finally addressed the SDL port as far sound is concerned,
and the SDL sound api is now supported again and properly this time.
I also added support for ALSA, OSS, libao, Portaudio and Pulseaudio.
Won't do DirectSound and/or WaveOut because fuck Windows :P
(but if you are interested, open a bug report)
Z80 core : When i added back the proprietary z80 core, i added version 3.4,
not the later version 3.9 that was improved by Exophase himself.
This should hopefully address the inaccuracy flaws that the old version had.
My mistake
I did a lot of cleaning too. I removed the old unsupported files
since they are now useless and you are better off using the
newer code instead.
