[xml/rdf views] handle case where the user hasn't read access to a relation (closes #1984598) The view shouldn't crash in such case. Also refactor xmlrelateditem view and its call on the way.

#! /bin/sh -e
 
case "$1" in
    remove)
	if [ -x "/etc/init.d/cubicweb-ctl" ]; then
	    invoke-rc.d cubicweb-ctl stop || true
	fi
    ;;
esac
 
#DEBHELPER#
 
exit 0