[cw-ctl] fix help message for schemadiff In global help (closes #2888538) The leading space make it appears on multiple line. The help content is a bit improved in the process.

#! /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