Very little problem with csv file import (prices are rounding too match)

[GolovinAlexx]

https://github.com/robcarver17/pysystemtrade/blob/b29a829bd4063ae94eb98580a2a6dcb7961c59e2/sysdata/csv/csv_futures_contract_prices.py#L149

I had problem with import csv files with FX prices which have four decimal places.
I changed column_series.round(2) at column_series.round(4) at this line and problem was solved.

[robcarver17]

fixed