mimic-iv version pulls directly from create.sql so we only have to maintain the postgres scripts (though, it does mean the sh file is no longer standalone, which is a disadvantage)
this updates the import to work with MIMIC-IV v2.2
shell script doesn't crash if there are other dirs with CSVs in them (but probably will still crash if the hosp/icu subdirs have CSV files for data not in MIMIC-IV)