Fix obsolete docstring for add_looping_task
The docstring was telling lies since changeset cae198371548
"add_looping_task can be used any time"
#! /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