[source schema] fix permission pb on cw_host_config_of relation + add composite on cw_source, so entities from a source are properly removed when the source is removed

#! /bin/sh -e

if [ -x "/etc/init.d/cubicweb-ctl" ]; then
    invoke-rc.d cubicweb-ctl restart || true
fi
 
 
#DEBHELPER#
 
exit 0