Allow `classifyVariants` to take scores by `aa_substitutions`

[ajgreaney]

@jbloom The classifyVariants function will not work on a dataframe of func_scores or escape_scores that have been calculated by aa_substitutions, as the input dataframe for this function must have columns named aa_substitutions, n_aa_substitutions, and n_codon_substitutions, and scores calculated by_aa_substitutions will lack the ‘n_codon_substitutions’ column.

There are hacky ways to get around this, but it would be great if the classifyVariants function would work directly on the output from func_scores or escape_scores when calculated by aa_substitutions.

[jbloom]

@ajgreaney, it should work if you set syn_as_wt=True (see here).

I think this is the correct behavior: if the statistic is being calculated by amino-acid substitutions, then the classification has to be categorizing synonymous variants as wildtype, so that should be explicitly specified.

I'm closing this issue, but feel free to re-open if this does not fix the problem.