nervous time to empty estimation on Dell machine

On my Dell machine, the time to empty estimation is heavily changing with each refresh of i3status, depending on the load currently on the machine. This was not present on my previous 2015-ThinkPad. I think low-pass filtering the current_now values from the battery could cure the problem as it would smooth short load peaks. If this would be preferred by you, I'd be happy to implement this feature and maybe get a hint how to implement such stateful behavior the best in this code base.