BF: allow csv conditions files to contain quoted commas

Changed importing of conditions files to use the pandas csv_reader rather than numpy's recfromcsv
NB this works BUT Builder's loop dialog still fails to deal with csv files containing quoted commas. That GUI aspect needs to be updated in a similar fashion but I'm not sure how.
i.e. at this stage, data.py can deal with these csv files, but Builder users can't select them.