[server] print backend exception if we fail to execute an sql script
It's more useful to see
could not open extension control file "/usr/share/postgresql/9.4/extension/postgis.control": No such file or directory
rather than merely
-> ERROR, skipping /usr/share/cubicweb/cubes/postgis/schema/_ext.postgres.sql
/var/log/cubicweb/*.log {
weekly
missingok
rotate 10
compress
delaycompress
notifempty
create 640 root adm
sharedscripts
postrotate
if [ -x /usr/sbin/invoke-rc.d ]; then \
invoke-rc.d cubicweb reload > /dev/null 2>&1; \
else \
/etc/init.d/cubicweb reload > /dev/null 2>&1; \
fi; \
endscript
}