Reduce thread downtime between BGC families

[adraismawur]

Currently there is a bit of single-threaded work being done between BGC families in pairwise comparison.

This is probably mostly these three components:

• Pre-processing of data. potential fix: process all data before doing pairwise comparison using multiple threads
• Post-processing of data. potential fix: first collect all comparisons, then do post-processing
• clustering. potential fix: do after collecting all pairwise comparisons instead of per family. use multiple threads