[primary view] delete PrimaryView.skip_none attribute (closes #2093250)
it was already broken anyway, since introduction of reledit (a while ago)
#! /bin/sh -e#if [ "$1" = configure ]; then if which install-docs >/dev/null 2>&1; then install-docs -i /usr/share/doc-base/cubicweb-doc fifi#DEBHELPER#exit 0