Hackaton/molgenis data integration

Basic command-line implementation of Molgenis data import
Requires 3 steps to use:
1 - run generateMetadataFiles.groovy to produce Molgenis protocol and feature metadata files
2 - edit the generated feature metadata file, removing or commenting the attribute we don't want to export
3 - run generateETLInputFiles.groovy to generate the data and column mapping files for ETL

This is using Molgenis rest api, and for now both scripts need to pass the jsessionId as an argument