Fix arraybuffer slice for old phantomjs
Fix arraybuffer slice for old phantomjs

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