Ignore NetCDF files in the data directory
Add a data directory (with a brief document outlining the data types). This repository omits the actual data files as they are too large, but the files may be made available elsewhere (and a note to that effect added to the README)
Change the data file path and fix some variable names
Add the beginnings of a unit test file for the get_POLCOMS_tsobc function to make sure it returns the same data as a 'known good' verison. This is by no means complete yet