Fix
* Check if disconnected before writing ([90](https://github.com/bdraco/yalexs-ble/issues/90)) ([`4096eef`](https://github.com/bdraco/yalexs-ble/commit/4096eefbe85903e2602aabe3b189489fae744a55))
* Do not force a resync if previous state was unknown ([89](https://github.com/bdraco/yalexs-ble/issues/89)) ([`84d82a7`](https://github.com/bdraco/yalexs-ble/commit/84d82a7300c4e49fe08aafa414236de4a84e56dd))