Add #savanna to eavesdrop

There are a lot of discussions of new features and new architecture in
the #savanna channel. Teams that are working on the project are from different
time zones, so, it'll be very helpful for us to have logs of this channel.

Change-Id: I96c1eb7ff05d24e048f26fcef739884371495e02

modules/openstack_project/manifests/eavesdrop.pp

@@ -29,6 +29,7 @@ class openstack_project::eavesdrop (
         '#openstack-meeting',
         '#openstack-meeting-alt',
         '#openstack-qa',
+        '#savanna',
     ],
     use_ssl   => 'True'
   }