Characteristics methods implementation
Characteristics methods implementation

Reviewers: przemek.lenart

Reviewed By: przemek.lenart

Differential Revision: https://phabricator.polidea.com/D1503

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