Wait before reconnecting log-pusher output.

* modules/openstack_project/files/logstash/log-pusher.py: If logstash
dies the TCP/UDP log-pusher.py outputs will not be able to reconnect.
Logstash appears to need about a minute to restart after a crash so wait
90 seconds after a socket exception before attempting to reconnect.

Change-Id: I61a31476ce5b521bcde02ac80566d693e0c89114
Reviewed-on: https://review.openstack.org/28364
Reviewed-by: Jeremy Stanley <fungi@yuggoth.org>
Approved: James E. Blair <corvus@inaugust.com>
Reviewed-by: James E. Blair <corvus@inaugust.com>
Tested-by: Jenkins