Add group vars to prep for os_tempest role changes
Add group vars to prep for os_tempest role changes

In review [1], we are updating os_tempest to function more like other
openstack-ansible roles.  However, to avoid breaking existing tooling
etc. we want to continue cloning tempest into /opt.  This commit simply
sets two group vars so that when [1] merges the integrated
openstack-ansible gate will continue to pass.

[1] https://review.openstack.org/#/c/310766/

Change-Id: Ie700c061cf0efa3d1fcda9e74618bb8c6e9ae371

cfarquhar/openstack-ansible,bunchc/openstack-ansible,major/openstack-ansible,cloudnull/os-ansible-deployment,major/openstack-ansible,yanyao/openstack-ansible,BjoernT/openstack-ansible,yanyao/newton,major/os-ansible-deployment,BjoernT/os-ansible-deployment,BjoernT/os-ansible-deployment,major/os-ansible-deployment,mancdaz/openstack-ansible,cfarquhar/openstack-ansible,stackforge/os-ansible-deployment,openstack/openstack-ansible,Logan2211/openstack-ansible,yanyao/newton,Logan2211/openstack-ansible,weezer/openstack-ansible,BjoernT/openstack-ansible,os-cloud/os-ansible-deployment,openstack/openstack-ansible,cloudnull/os-ansible-deployment,weezer/openstack-ansible,bunchc/openstack-ansible,os-cloud/os-ansible-deployment,stackforge/os-ansible-deployment,yanyao/openstack-ansible,mancdaz/openstack-ansible,robb-romans/openstack-ansible,robb-romans/openstack-ansible,BjoernT/os-ansible-deployment