Version 0.5 : Initial release.

Version 0.9 : Sound support.

Version 0.95: Scrolltext made up-to-date.
              Improved Makefile.
	      Cheat codes handling.
	      Bug fixes with the sound effects.
	      Cleaned permissions of the source files.

Version 0.98: vsync() is now directly using I/O ports instead of
              svgalib because of incompatibilities with modern adapters.
              ioperm() is called in order to get access to I/O ports on
              modern Linux kernels.
              Various minor code fixups.
