MB-100 Make menelaus_ui_auth ets tables protected.

For easier debugging.

Change-Id: I0a92fa424c0f057c7eefb5e06b791aad1dbcd870
Reviewed-on: http://review.couchbase.org/28604
Tested-by: Aliaksey Artamonau <aliaksiej.artamonau@gmail.com>
Reviewed-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>