add bokeh thumbnail
add bokeh thumbnail

Jay-Oh-eN/nbviewer,christophelec/nbviewer,imsparsh/nbviewer,AlfiyaZi/nbviewer,christophelec/nbviewer,thomasyu888/nbviewer,bollwyvl/nbviewer,AlfiyaZi/nbviewer,Sage-Bionetworks/nbviewer,roxyboy/nbviewer,imsparsh/nbviewer,Sage-Bionetworks/nbviewer,bollwyvl/nbviewer,iamjakob/nbviewer,iamjakob/nbviewer,thomasyu888/nbviewer,Jay-Oh-eN/nbviewer,roxyboy/nbviewer