Feature Request: Option to use last_updated instead of last_changed attribute for timestamping

[yuejon]

Would like to request the option to use the last_updated attribute instead of last_changed attribute as some entities like climate entities do not update the last_chaged timestamp when there are action or attribute updates. For example, if my thermostat is set to cool, I won't change it for the rest of the season and the state remains as cool the whole time, but the action attribute updates when the HVAC is running or when the temperature changes.