We have two similar projects in [py lino_noi.projects] : bs3 and public. One uses [py lino.modlib.bootstrap3] as default_ui, the other [py lino_noi.projects.public]. Discuss and document their differences. Decide whether one of them can go away. NB for [url bugs.lino-framework.org] we currently use [py lino.modlib.bootstrap3].