add an explicit check for ref seq start < end
add an explicit check for ref seq start < end

GMOD/jbrowse,GMOD/jbrowse,Arabidopsis-Information-Portal/jbrowse,limeng12/jbrowse,limeng12/jbrowse,nathandunn/jbrowse,erasche/jbrowse,GMOD/jbrowse,limeng12/jbrowse,erasche/jbrowse,Arabidopsis-Information-Portal/jbrowse,Arabidopsis-Information-Portal/jbrowse,GMOD/jbrowse,nathandunn/jbrowse,nathandunn/jbrowse,erasche/jbrowse,nathandunn/jbrowse,GMOD/jbrowse,erasche/jbrowse,erasche/jbrowse,erasche/jbrowse,limeng12/jbrowse,Arabidopsis-Information-Portal/jbrowse,limeng12/jbrowse,erasche/jbrowse,erasche/jbrowse,nathandunn/jbrowse,Arabidopsis-Information-Portal/jbrowse,Arabidopsis-Information-Portal/jbrowse,limeng12/jbrowse,limeng12/jbrowse,Arabidopsis-Information-Portal/jbrowse,limeng12/jbrowse