* new elapsed attribute giving the elapsed time since the previous msg
* configurable elapsed attribute
* Update deviceReceive.js
* Update deviceReceive.js
* feat(device_receive): stop caching `forgotten` and `keyerror` properties
After this change, the `forgotten` and `keyerror` properties as emitted
by the Xiaomi Vima Smart Lock will stop being cached. Previously they
were mostly useless, because after they were set to `true`, they were
never being unset or set back to `false` upon a successful unlock.
Close#666
* chore(device_receive): order uncached properties lexicographically
As the list of uncached properties grows over time, it could be
useful to order them lexicographically. This will make life easier
to any developer looking for a particular property in the list, and
in overall makes things look tidier.