Added joker selling (still no animation) + fixed SpriteObject constructor focused bug

include/game.h

@@ -23,6 +23,7 @@
 #define PEEK_DECK KEY_L // Not implemented
 #define SORT_HAND KEY_R
 #define PAUSE_GAME KEY_START // Not implemented
+#define SELL_KEY KEY_L
 
 enum GameState
 {
@@ -90,4 +91,4 @@ List*           get_jokers(void);
 
 int get_num_discards_remaining(void);
 
-#endif // GAME_H
+#endif // GAME_H