* Clean up use of get_characteristic_types
* Get rid of get_hk_char_value helper
* Get rid of _update_fn callbacks
* Call async_write_has_state directly as async_state_changed doesnt do anything any more
* Bump aiohomekit to get better reconnection handling and cleaner shutdowns.
* Read the ACTIVE characteristic and set ok/problem state
Also gets test coverage to 100%.