Fix FTB.

Add support of private packs.
Fix instance ID problems related to FTB instances.

logic/LegacyFTBInstance.h

@@ -10,4 +10,5 @@ public:
 							   QObject *parent = 0);
 	virtual QString getStatusbarDescription();
 	virtual bool menuActionEnabled(QString action_name) const;
+	virtual QString id() const;
 };