add Lua methods

stepmania/src/StageStats.cpp

@@ -89,10 +89,12 @@ public:
 	LunaStageStats() { LUA->Register( Register ); }
 
 	static int GetPlayerStageStats( T* p, lua_State *L )	{ p->m_player[IArg(1)].PushSelf(L); return 1; }
+	static int GetGameplaySeconds( T* p, lua_State *L )		{ lua_pushnumber(L, p->fGameplaySeconds); return 1; }
 
 	static void Register(lua_State *L)
 	{
 		ADD_METHOD( GetPlayerStageStats )
+		ADD_METHOD( GetGameplaySeconds )
 		Luna<T>::Register( L );
 	}
 };