Added Cartfile to support Carthage dependency manager.
Added Cartfile to support Carthage dependency manager.

Fitbit/RxBluetoothKit,Polidea/RxBluetoothKit,Fitbit/RxBluetoothKit,proxyco/RxBluetoothKit,Polidea/RxBluetoothKit,Polidea/RxBluetoothKit,Fitbit/RxBluetoothKit,proxyco/RxBluetoothKit