For the MAX_12 pseudo-germline, the FineSegmenter now calls override_rep5_rep3_from_labels,
and then continue by the regular way.

Note that IKmerStore:getLabel() returns *one* Fasta file, even when several files were used
for the same KmerAffect, such as in TRD+ or IGK+. In these cases, the FineSegmenter will
probably fail when the bad Fasta file is returned.