reference: a two-column format genetic dataset, with "repunit", "collection", and "indiv" columns, as well as a "sample_type" column that has some "reference" entries
gen_start_col: the first column of genetic data in reference
preCompiledParams: Users should never use this option. It is here only so that this function can be called on a precompiled set of parameters with infer_mixture. Don't use this, unless you are one of the package developers...
alle_freq_prior: a one-element named list specifying the prior to be used when generating Dirichlet parameters for genotype likelihood calculations. Valid methods include "const", "scaled_const", and "empirical". See ?list_diploid_params