New release. Works on Irix

I have written some more code on this game since I have an C couse in school. Most of the changes are internal and not visible to the user. For a list of changes see the changelog.

The game now works on Irix. I used the standard compiler and make utility for Irix. I had to code an strrev function, since such a function doesn't exist in ANSI C. I also had to make a new Makefile since my current for Linux is for Gnumake.