Various improvements to speed up and avoid duplicates
Various improvements to speed up and avoid duplicates

HazyResearch/dd-genomics,rionda/dd-genomics,HazyResearch/dd-genomics,HazyResearch/dd-genomics,HazyResearch/dd-genomics,rionda/dd-genomics,amwenger/dd-genomics,amwenger/dd-genomics,HazyResearch/dd-genomics,amwenger/dd-genomics