use token stored in meta header in maybe_refresh_token
use token stored in meta header in maybe_refresh_token

it is always there if called from UI and slightly easier to obtain

Change-Id: I5f40ed9949f8b463b4f6998356382f631c70ef5a
Reviewed-on: http://review.couchbase.org/89593
Tested-by: Artem Stemkovski <15a0730a27c69f62ab86f2b6c639fca202166c02@couchbase.com>
Well-Formed: Build Bot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>
Reviewed-by: Aliaksey Artamonau <ce14b1c16e0fd654f926118eb8addbec5aff4ffa@couchbase.com>

membase/ns_server,membase/ns_server,membase/ns_server,membase/ns_server,membase/ns_server,membase/ns_server