Tile fixes and BCD substraction fix
Added loading of 16x16 and 8x8 sprites in asset loader.
Fixed a bug with sprites not shown when posY >= height - spriteSize or posX >= width - spriteSize.
Fixed issue with WindowX and large tiles. Also fixed the off by 1 issue with small tiles.
When resetting the machine, reset the tilestride...
Fixed SBC (substraction) bug when in decimal mode and the subtrahend is larger than the minuend (difference is negative).