mame_regtest
(c) Copyright 2005-2014 by Oliver Stoeneberg

http://www.breaken.de/mame_regtest

notes:
	- you need libxml2-2.6.27 to compile this
	- you need zlib 1.2.3 to compile this
	- if you are using a compiler without dirent.h you need dirent API 1.11 to compile this: http://www.softagalleria.net/dirent.php
	- if you are using a system with big-endian byte-order you have to comment the LITTLE_ENDIAN and uncomment the BIG_ENDIAN define
	- XPath tutorial: http://www.zvon.org/xxl/XPathTutorial/General/examples.html

MAME/MESS returncodes:
          1 - terminated / ???
          2 - missing roms
          3 - assertion / fatalerror
          4 - no image specified (MESS-only)
          5 - no such game
          6 - invalid config
        128 - ???  
        100 - exception
-1073741819 - exception (SDLMAME/SDLMESS)

mame_regtest returncodes:
	0 - OK
	1 - error

pngcmp:
	- is built as part of the MAME/MESS "tools" target - please copy it from an existing installation to the mame_regtest folder
	- retuncodes:
		0 - images are identical - no diff written
		1 - images are identical - diff written
	   -1 - an error occured