- Add mfdb_na_group function to put NAs in the their own group
- Remove remaining cs_taxonomy differences, simplify code
- mfdb_sample_rawdata now will group into a list, like other sample functions
Schema changes:
- age now stored as REAL
- areacell size now stored as REAL
- Allow gear taxonomy to be changed
- Allow the species schema to be changed also
- Add tow_end_latitude/tow_end_longitude/tow_start/tow_duration
- Add gear_mesh_size/gear_mesh_size_min/gear_mesh_size_max