CERIDWEN quickstart SSP grids

ssp_data.h5: FSPS v3.2 via python-fsps 0.4.7, MIST isochrones, MILES spectra, Chabrier (2003) IMF (imf_type=1) isoc_type : mist spec_library : miles fsps_kwargs : {'imf_type': 1} schema_version : 1.0 ssp_lgmet : 12 points [-4.35, -1.35] ssp_lg_age_gyr : 107 points ssp_wave : 5994 points [91, 100000000] AA ssp_data_bpass.h5: BPASS v2.x pre-integrated SSPs (IMF fixed by BPASS) isoc_type : bpss spec_library : bpass fsps_kwargs : {} schema_version : 1.0 ssp_lgmet : 12 points [-4.00, -1.40] ssp_lg_age_gyr : 43 points ssp_wave : 15000 points [1, 100000000] AA