changed clans clustering based on the changes we discussed:

1. Distance is average of average of pairwise distances between family members
2. Two arguments for clan cutoff: first is the cutoff value used for family assignment, second is the cutoff value for clans clustering
3. Fixed bug in distance calculation (max of similarities instead of famSimilarities)
4. Added clan_cutoff value to cutoffs if it's not there yet
5. Clans TSV file
6. Reworked clustering TSV file to take advantage of data structures