MB-9462: renamed cas_config/2 to cas_remote_config/2

To better reflect it's meaning. I.e. it's not announcing config
changes in ns_config_events_local.

Change-Id: I001e7d0aff446e5f73697766cedeeb992ed15f48
Reviewed-on: http://review.couchbase.org/30114
Tested-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
Reviewed-by: Artem Stemkovski <artem@couchbase.com>