Revert "Round 2-2 of this."

This reverts commit 0ae4183f7b.

src/GameState.h

@@ -98,6 +98,7 @@ public:
 	 * Note that coins are not "credits". One may have to put in two coins 
 	 * to get one credit, only to have to put in another four coins to get
 	 * the three credits needed to begin the game. */
+	BroadcastOnChange<int>			m_iCoins;
 	bool			m_bMultiplayer;
 	int				m_iNumMultiplayerNoteFields;
 	bool DifficultiesLocked() const;
@@ -120,6 +121,8 @@ public:
 	 * @brief Determine if a second player can join in at this time.
 	 * @return true if a player can still enter the game, false otherwise. */
 	bool	PlayersCanJoin() const;
+	int 	GetCoinsNeededToJoin() const;
+	bool	EnoughCreditsToJoin() const { return m_iCoins >= GetCoinsNeededToJoin(); }
 	int		GetNumSidesJoined() const;
 
 	const Game*	GetCurrentGame();