improve massive deletion performance change hooks.integrity._DelayedDeleteOp implementation to give it a chance of processing the entities by chunks of reasonnable size (500 entities at a time) adapt ssplanner.DeleteEntitiesStep to call a variant of glob_delete_entity with several entities. That variant calls all the before_delete_entities hooks in one go, then performs the deletion, and then calls all the after_delete_entities hooks. The deletion is performed by grouping together entities by etype and by source. adapt the HooksManager to call the hooks on a list of entities instead of on a single entity. adapt the sources to be able to delete several entities of the same etype at once. changed the source fti_(un)index_entity methods to fti_(un)index_entities taking a collection of entities.

/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
}