Changes
TODO :
* correct http://www.cpcwiki.eu/index.php/Creating_images_for_the_Amstrad
* add http://www.mapeditor.org/; http://www.intensity.org.uk/samcoupe/pyz80.html
* https://code.google.com/p/retrodev/ or new code adapted for z88dk , ( see http://www.libpng.org/pub/png/book/toc.html )
perharps possible to load directly no compressed ( deflate -cf http://sourceforge.net/projects/samflate/ ) png ( removing header ?)
