@Override
                public void run() {
                    bluetoothGatt.disconnect();
                }
TODO: [DS] 09.02.2016 This operation makes the queue to block until disconnection - maybe it would be better if it would not?
What would happen then if a consecutive call to BluetoothDevice.connectGatt() would be made? What BluetoothGatt would be returned?
1. A completely fresh BluetoothGatt - would work with the current flow
2. The same BluetoothGatt - in this situation we should probably cancel the pending BluetoothGatt.close() call
rxandroidble/src/main/java/com/polidea/rxandroidble2/internal/operations/DisconnectOperation.java