convert pheno_c to bitfield
groupdist bugfix
prepare to add precomputation to groupdist
move groupdist to separate function
accelerated groupdist complete
about to make sex_info into 2 bitfields
sex_info cleanup done
closer to proper X handling
freqs haploid handling
bugfix
minor --freq printing cleanup
defend against different eolns
--set-hh-missing + --make-bed
--recode transpose + --set-hh-missing