MB-11694: default 'upload to' hostname for enterprise

Change-Id: I29cf5b299a7efc305ef12b308beacd6caaa8f421
Reviewed-on: http://review.couchbase.org/39490
Reviewed-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
Tested-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>