MB-10859: made /pools/nodes be alias of /pools/default for now

I.e. because our docs exposed /pools/nodes.

Change-Id: I00204a3bf6c5cc25d0700a51aacae3fafc5a53c4
Reviewed-on: http://review.couchbase.org/35749
Tested-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
Reviewed-by: Aliaksey Artamonau <aliaksiej.artamonau@gmail.com>