MB-26636: expose module descriptors key
MB-26636: expose module descriptors key

Change-Id: If3196d9d0302e2bce99373bc6f21b98c3ad28c06
Reviewed-on: http://review.couchbase.org/89254
Well-Formed: Build Bot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>
Reviewed-by: Artem Stemkovski <15a0730a27c69f62ab86f2b6c639fca202166c02@couchbase.com>
Tested-by: Artem Stemkovski <15a0730a27c69f62ab86f2b6c639fca202166c02@couchbase.com>

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