Fix Replica Lag reset to 0 at the turn of a day

[oliver-k-yeh]

total_seconds is more accurate then seconds

import datetime
x = datetime.datetime(2020,1,2)
y = datetime.datetime(2020,1,4)
(x-y).seconds  # 2
(x-y).total_seconds() # -172800.0

You are probably asking - "Why in the world do you have a replica set that has a lag of over a day?"

Well, we have such a long lag when we do initial syncs X-)