tweak help-box key handling so that ctrl, shift, and alt don't close the box
tweak help-box key handling so that ctrl, shift, and alt don't close the box

GreggHelt2/apollo-test,limeng12/jbrowse,erasche/jbrowse,Arabidopsis-Information-Portal/jbrowse,GMOD/jbrowse,GMOD/jbrowse,GreggHelt2/apollo-test,limeng12/jbrowse,nathandunn/jbrowse,GreggHelt2/apollo-test,GreggHelt2/apollo-test,erasche/jbrowse,SuLab/jbrowse,SuLab/jbrowse,nathandunn/jbrowse,GreggHelt2/apollo-test,Arabidopsis-Information-Portal/jbrowse,GMOD/jbrowse,limeng12/jbrowse,erasche/jbrowse,limeng12/jbrowse,nathandunn/jbrowse,Arabidopsis-Information-Portal/jbrowse,erasche/jbrowse,nathandunn/jbrowse,GMOD/jbrowse,erasche/jbrowse,SuLab/jbrowse,limeng12/jbrowse,erasche/jbrowse,GMOD/jbrowse,Arabidopsis-Information-Portal/jbrowse,limeng12/jbrowse,Arabidopsis-Information-Portal/jbrowse,erasche/jbrowse,SuLab/jbrowse,igemsoftware/Shenzhen_BGIC_0101_2013,erasche/jbrowse,igemsoftware/Shenzhen_BGIC_0101_2013,SuLab/jbrowse,limeng12/jbrowse,igemsoftware/Shenzhen_BGIC_0101_2013,Arabidopsis-Information-Portal/jbrowse,Arabidopsis-Information-Portal/jbrowse,limeng12/jbrowse,igemsoftware/Shenzhen_BGIC_0101_2013,igemsoftware/Shenzhen_BGIC_0101_2013,igemsoftware/Shenzhen_BGIC_0101_2013,SuLab/jbrowse,GreggHelt2/apollo-test,SuLab/jbrowse,nathandunn/jbrowse,igemsoftware/Shenzhen_BGIC_0101_2013,GreggHelt2/apollo-test,igemsoftware/Shenzhen_BGIC_0101_2013