Currently, we register snitch API in set_server_gossip_settle() which
waits until a node has joined the cluster. This makes 'nodetool status'
not properly show the status of a joining node. Fix the issue by
registering snitch API earlier.
Fixes#1269.
Message-Id: <1463576381-15484-1-git-send-email-penberg@scylladb.com>