make the coverage scores in BaseCoverage be NestedFrequencyTables, use that to provide info on which strands contribute to specific SNP counts
make the coverage scores in BaseCoverage be NestedFrequencyTables, use that to provide info on which strands contribute to specific SNP counts

GMOD/jbrowse,limeng12/jbrowse,Arabidopsis-Information-Portal/jbrowse,erasche/jbrowse,GMOD/jbrowse,SuLab/jbrowse,igemsoftware/Shenzhen_BGIC_0101_2013,GMOD/jbrowse,erasche/jbrowse,igemsoftware/Shenzhen_BGIC_0101_2013,limeng12/jbrowse,igemsoftware/Shenzhen_BGIC_0101_2013,erasche/jbrowse,GMOD/jbrowse,Arabidopsis-Information-Portal/jbrowse,igemsoftware/Shenzhen_BGIC_0101_2013,erasche/jbrowse,Arabidopsis-Information-Portal/jbrowse,nathandunn/jbrowse,limeng12/jbrowse,nathandunn/jbrowse,erasche/jbrowse,igemsoftware/Shenzhen_BGIC_0101_2013,SuLab/jbrowse,Arabidopsis-Information-Portal/jbrowse,limeng12/jbrowse,erasche/jbrowse,limeng12/jbrowse,igemsoftware/Shenzhen_BGIC_0101_2013,Arabidopsis-Information-Portal/jbrowse,igemsoftware/Shenzhen_BGIC_0101_2013,nathandunn/jbrowse,nathandunn/jbrowse,igemsoftware/Shenzhen_BGIC_0101_2013,erasche/jbrowse,SuLab/jbrowse,limeng12/jbrowse,Arabidopsis-Information-Portal/jbrowse,GMOD/jbrowse,Arabidopsis-Information-Portal/jbrowse,limeng12/jbrowse,SuLab/jbrowse,SuLab/jbrowse,SuLab/jbrowse,SuLab/jbrowse,limeng12/jbrowse,nathandunn/jbrowse,erasche/jbrowse