SNP datasets generated by DArT include fragments with more than one SNP and
record them separately with the same CloneID (=AlleleID). These multiple SNP
loci within a fragment (secondaries) are likely to be linked, and so you may
wish to remove secondaries.
This script filters out all but the first sequence tag with the same CloneID
after ordering the genlight object on based on repeatability, avgPIC in that
order (method='best') or at random (method='random').
The filter has not been implemented for tag presence/absence data.