Autofire and Custom Buttons patch

[yatzr]

I had seen a thread previously stating that autofire and custom buttons will probably never be included in groovymame, and I'm cool with that, but my wrists suck and I gotta have it.  I really like the way mameplus does it, so I extracted the autofire + custom buttons code into a separate patch.  It turned out to be pretty easy.  This patch will work on both vanilla mame and groovymame.  The line numbers might get off, but the patching utility should be able to handle it.  Only thing to note...mameplus uses some fancy icons in the menu for custom buttons.  I didn't bother trying to extract all that code, so instead of the fancy 1, 2, 3 etc icons, you'll see "_a", "_b", "_c" etc.  I've tested it with a build of groovymame 155 and it seemed to work just fine.  I don't plan on maintaining this patch forever, I just thought I'd share it since I'm sure others would like to make use of it.

[cools]

I just use the cheat file, most of the games needing autofire have it with that.

[Whipon]

Best way I found to have autofire in every game was by hardware. I did a tiny circuit with a NE555 timer, that I enable or disable by a simple switch.
It works like a charm ñ_ñ.