Increase mongodb_conn_validator timeout to 600
Increase mongodb_conn_validator timeout to 600

This will increase the mongodb_conn_validator timeout from 60 secs
(the default) to 600 secs; it should take much less in normal
circumstances to start mongod but nodes might not be starting it all
at the same time so we use a larger timeframe for the availablity
checks.

Change-Id: I0ee210be94b33d1c08d67f287aa745743a6649d3

bcrochet/tripleo-heat-templates,trozet/tripleo-heat-templates,trozet/opnfv-tht,wyg3958/tripleo-heat-templates,dprince/tripleo-heat-templates,dprince/tripleo-heat-templates,trozet/opnfv-tht,openstack/tripleo-heat-templates,rdo-management/tripleo-heat-templates,rdo-management/tripleo-heat-templates,openstack/tripleo-heat-templates,trozet/tripleo-heat-templates,trozet/opnfv-tht,bcrochet/tripleo-heat-templates,wyg3958/tripleo-heat-templates,bcrochet/tripleo-heat-templates