osa: add tool to cleanup host

This tool will contain more things eventually but for
now it'll just cater for a list of things to clean up
in environments with low disk space.

Change-Id: I84568f4de20c6c38c96e7a4c1fcad6d5c949d205

openstack-ansible/cleanup_host.sh

@@ -0,0 +1,7 @@
+#!/bin/bash
+
+# This script reclaims space on a host that might
+# be low on disk space by getting rid of logs and
+# extra data.
+
+find /openstack/log/ -type f | xargs -n1 truncate -s0