Changing two text type column to varchar with PersonLink persistence to try to gain some speed.
Deleting unnecessary imports
Don't sort record pairs and don't set lower and upper bounds in case of CBF scoring. The bounds are tunable anyway, the DB can be examined (ORDER BY weight). The purpose is to try to speed up persistence.
First sketch of speeding up Jaccard and Dice Binary metrics with hamming weight lookup tables (hamming weight, intersect hamming weight, union hamming weight). This won't help the persistence speed though of CBF linkage.