Adds module to retrieve session data given a start date and end date, and return a CSV file
As per the OCPI DateTime requirements, these date formats are accepted:
2015-06-29T20:39:09Z
2015-06-29T20:39:09
2016-12-29T17:45:09.2Z
2016-12-29T17:45:09.2
2018-01-01T01:08:01.123Z
2018-01-01T01:08:01.123