Documentation and little code refactoring

This is is just a little update. The program works exactly as before and the changes are either small code refactoring and mostly about documentation. The README got slimmer and now there is a Wiki, which will be expanded soon.

There are no big plans in changing the program itself or adding too many features. The core application should stay simple and lightweight as possible. However it still don't support many of the features the original retroarch commandline does.

As usual you just need to download "enjoy_0.1.1.tar.gz". The other archive "enjoyd.gz" is much bigger and slower and it's purpose is for debugging.