Plausibility check in water consumption

[KirsusKapsus]

Hey guys,

first of all great work you've don here! I've got two (until now) of these little fountains and flashed them both with your firmware for a decent HA integration with some nice charts. Now I'm able to add up the consumption of the different fountains and get the summed up daily consumtion (which was not the case in the petlibro app).

My Issue #1: When i remove the tank, it counts the massive amount of removed weight as consumed water. I would like to add a plausibility criterea, that does not count the waterconsumption when weight drops below the "min_water_level" level defined in the calibration. In my eyes that would prevent counting anything when the tank is removed for a refill or cleaning. A second optional plausiblility level for a "max_amount" could be a fixed number or parameter.

I like the two point calibration btw! One more step, but more accurate as the correct range (min/max waterlevel is taken into account as I am not yet sure about the linearity of the scale, I'll check that in the upcoming days). is applied here.