It is useful to debug differences between implementations, e.g.:
```sh
$ while ./create_measurements.sh 1000 && diff <(./calculate_average_royvanrijn.sh 2>/dev/null | ./tocsv.sh) <(./calculate_average.sh 2>/dev/null | ./tocsv.sh) ; do echo OK; done
Created file with 1,000 measurements in 50 ms
60c60
< Bucharest;-2.9;2.9;6.1
---
> Bucharest;-2.9;2.8;6.1
265c265
< Petropavlovsk-Kamchatsky;0.9;9.3;17.7
---
> Petropavlovsk-Kamchatsky;0.9;9.2;17.7
```
For #14
