sahara IRC notifications: add a repo and future branches
sahara IRC notifications: add a repo and future branches

- display the events also for openstack-ansible-os_sahara;
- a bit early, but let's track the known future versions (queens
  and rocky).

Change-Id: I3baa08aca1c9b6fdf37c4a7cc972c60b2d18cb25

openstack-infra/project-config,openstack-infra/project-config