MB-8145: don't expose bucket sasl passwords to read-only admin

Change-Id: I53d65976d1511ce5fcf12dda7ba47c88ab4f593d
Reviewed-on: http://review.couchbase.org/28130
Reviewed-by: Aliaksey Artamonau <aliaksiej.artamonau@gmail.com>
Tested-by: Aliaksey Artamonau <aliaksiej.artamonau@gmail.com>
MB-100: adapted run_in_ns.rb for babysitter VM changes

I've updated help text and made sure things work (but somehow only if
you manually assign correct address via setup wizard).

Change-Id: I16d3fe79806935221fa51c8c84818a15e73acdbb
Reviewed-on: http://review.couchbase.org/28198
Tested-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
Reviewed-by: Aliaksey Artamonau <aliaksiej.artamonau@gmail.com>