To move the avatar use the arrow keys. To enter a game move up the ladder.
The right hand ladder is for the binary game and the left hand ladder is for
the encryption game. 

In the binary game the desired score is shown at the top. Switch the bulbs
on and off until the correct score is displayed. The doors will then unlock and
the game will be completed.

In the encryption game, the displayed word must be unscrambled by pressing the
buttons which surround the word.  The arrow keys directly above and below 
each letter will shift it up and down the alphabet.  There is a reset button
on the left, and a hint button on the right, which will display a hint on
the screen in the background. When the correct word is displayed, the doors
will open.



Other keys:
Space - Action key: press buttons, switches and so on.
Esc   - Quit the game.

Libraries needed:
SDL2
SDL2 image
SDL2 mixer