CGE2: Add Sfinx

This pull request is about CGE2 engine, which is responsible for handling the game Sfinx. (http://www.mobygames.com/game/dos/sfinx)
The engine is developed by me, Strangerke, dreammaster and digitall, and we also got help with the translation from criezy.
All the work was done for my GSoC project this year, you can read more about our progress on my blog: http://urukgsoc.blogspot.hu/
The engine is complete, but the English translation is still in a WIP state and needs some polishing. We are currently working on that.
There'll might still be some minor bugfix concerning memory leak problems (the most of them are dealt with) and a bigger addition to the detection when the translation is complete.
Every comment is welcome, please don't hold anything back! :)
This looks odd. One would expect to return an error in case _error is set or _readStream has detected an error. So, it seems "||" should be used here. Then again, it seems the CGE code suffers from the same oddity.