Set upper bound in comparison with the control in the bridge reachability timeline
In the bridge reachability exported data format we compare the experiment measurement with the closest measurement that was done from the control vantage point.
The problem with the current approach is that in some cases the closest measurement (on the time scale), may be various days in the future or in the past leading to inconsistent results (we mark them as blocked, while they may have been offline at that time).
To avoid this we should set an upper bound on how distant the control can be as a maximum value and if there is no control measurement that is close enough we should say that we can't conclude anything (perhaps mark it with some distinctive color).
The function in question is the following: https://github.com/TheTorProject/ooni-pipeline/blob/master/ooni/pipeline/measurements.py#L4