[web] add a Forbidden exception
This is similar to the Unauthorized exception, but generates a 403 error
instead of a 401 (Unauthorized)
#! /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