feat: add grid & level seggregation per leveltype and Era5/Land

Tables/era5-cmor-tables/Tables/ERA5Land_1hr_sfc.json

Tables/era5-cmor-tables/Tables/ERA5Land_day_sfc.json

Tables/era5-cmor-tables/Tables/ERA5Land_mon_sfc.json

Tables/era5-cmor-tables/Tables/ERA5_1hr_ml.json

Tables/era5-cmor-tables/Tables/ERA5_1hr_pl.json

Tables/era5-cmor-tables/Tables/ERA5_1hr_sfc.json

Tables/era5-cmor-tables/Tables/ERA5_day_ml.json

Tables/era5-cmor-tables/Tables/ERA5_day_pl.json

Tables/era5-cmor-tables/Tables/ERA5_day_sfc.json

Tables/era5-cmor-tables/Tables/ERA5_fx_ml.json

Tables/era5-cmor-tables/Tables/ERA5_fx_pl.json

Tables/era5-cmor-tables/Tables/ERA5_fx_sfc.json

Tables/era5-cmor-tables/Tables/ERA5_mon_ml.json

Tables/era5-cmor-tables/Tables/ERA5_mon_pl.json

Tables/era5-cmor-tables/Tables/ERA5_mon_sfc.json

src/converter.py