Right now, we only index logstash.txt, which is fine now. The file is ~100K. But this file doesn't context OpenStack services logs, and other logs we want to index, so we can use elastic-recheck more powerfully. So this patch index both undercloud & subnodes (overcloud) .log.txt files present in /var/log/*. Change-Id: Id5b9be6130e4e4506418a254a5e57e105fa4d03c